Refactor Error enum usage to consistently be qualified

19 files changed, 139 insertions, 161 deletions

diff --git a/components/script/dom/bindings/structuredclone.rs b/components/script/dom/bindings/structuredclone.rs
index 663a17cd309..68757f5ed29 100644
--- a/components/script/dom/bindings/structuredclone.rs
+++ b/components/script/dom/bindings/structuredclone.rs
@@ -5,8 +5,7 @@
 //! This module implements structured cloning, as defined by [HTML]
 //! (https://html.spec.whatwg.org/multipage/#safe-passing-of-structured-data).
 
-use dom::bindings::error::Error::DataClone;
-use dom::bindings::error::Fallible;
+use dom::bindings::error::{Error, Fallible};
 use dom::bindings::global::GlobalRef;
 use js::glue::JS_STRUCTURED_CLONE_VERSION;
 use js::jsapi::{HandleValue, MutableHandleValue};
@@ -34,7 +33,7 @@ impl StructuredCloneData {
         };
         if result == 0 {
             unsafe { JS_ClearPendingException(cx); }
-            return Err(DataClone);
+            return Err(Error::DataClone);
         }
         Ok(StructuredCloneData {
             data: data,
diff --git a/components/script/dom/canvasgradient.rs b/components/script/dom/canvasgradient.rs
index 527b881778d..8f8ad3cc99f 100644
--- a/components/script/dom/canvasgradient.rs
+++ b/components/script/dom/canvasgradient.rs
@@ -6,8 +6,7 @@ use canvas_traits::{CanvasGradientStop, FillOrStrokeStyle, LinearGradientStyle,
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::CanvasGradientBinding;
 use dom::bindings::codegen::Bindings::CanvasGradientBinding::CanvasGradientMethods;
-use dom::bindings::error::Error::{IndexSize, Syntax};
-use dom::bindings::error::ErrorResult;
+use dom::bindings::error::{Error, ErrorResult};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::Root;
 use dom::bindings::num::Finite;
@@ -47,12 +46,12 @@ impl CanvasGradientMethods for CanvasGradient {
     // https://html.spec.whatwg.org/multipage/#dom-canvasgradient-addcolorstop
     fn AddColorStop(&self, offset: Finite<f64>, color: String) -> ErrorResult {
         if *offset < 0f64 || *offset > 1f64 {
-            return Err(IndexSize);
+            return Err(Error::IndexSize);
         }
 
         let color = match parse_color(&color) {
             Ok(color) => color,
-            _ => return Err(Syntax)
+            _ => return Err(Error::Syntax)
         };
 
         self.stops.borrow_mut().push(CanvasGradientStop {
diff --git a/components/script/dom/canvasrenderingcontext2d.rs b/components/script/dom/canvasrenderingcontext2d.rs
index 9a6443c052f..150369a97fa 100644
--- a/components/script/dom/canvasrenderingcontext2d.rs
+++ b/components/script/dom/canvasrenderingcontext2d.rs
@@ -15,8 +15,7 @@ use dom::bindings::codegen::Bindings::ImageDataBinding::ImageDataMethods;
 use dom::bindings::codegen::InheritTypes::NodeCast;
 use dom::bindings::codegen::UnionTypes::HTMLImageElementOrHTMLCanvasElementOrCanvasRenderingContext2D;
 use dom::bindings::codegen::UnionTypes::StringOrCanvasGradientOrCanvasPattern;
-use dom::bindings::error::Error::{IndexSize, InvalidState, Syntax};
-use dom::bindings::error::Fallible;
+use dom::bindings::error::{Error, Fallible};
 use dom::bindings::global::{GlobalField, GlobalRef};
 use dom::bindings::js::{JS, LayoutJS, Root};
 use dom::bindings::num::Finite;
@@ -252,7 +251,7 @@ impl CanvasRenderingContext2D {
                         let size = Size2D::new(size.width as f64, size.height as f64);
                         (data, size)
                     },
-                    None => return Err(InvalidState),
+                    None => return Err(Error::InvalidState),
                 };
                 let dw = dw.unwrap_or(image_size.width);
                 let dh = dh.unwrap_or(image_size.height);
@@ -272,7 +271,7 @@ impl CanvasRenderingContext2D {
                   dx: f64, dy: f64, dw: Option<f64>, dh: Option<f64>) -> Fallible<()> {
         // 1. Check the usability of the image argument
         if !canvas.is_valid() {
-            return Err(InvalidState)
+            return Err(Error::InvalidState)
         }
 
         let canvas_size = canvas.get_size();
@@ -286,7 +285,7 @@ impl CanvasRenderingContext2D {
         let (source_rect, dest_rect) = self.adjust_source_dest_rects(image_size, sx, sy, sw, sh, dx, dy, dw, dh);
 
         if !is_rect_valid(source_rect) || !is_rect_valid(dest_rect) {
-            return Err(IndexSize)
+            return Err(Error::IndexSize)
         }
 
         let smoothing_enabled = self.state.borrow().image_smoothing_enabled;
@@ -297,7 +296,7 @@ impl CanvasRenderingContext2D {
         } else { // Source and target canvases are different
             let context = match canvas.get_or_init_2d_context() {
                 Some(context) => context,
-                None => return Err(InvalidState),
+                None => return Err(Error::InvalidState),
             };
 
             let renderer = context.r().get_ipc_renderer();
@@ -326,7 +325,7 @@ impl CanvasRenderingContext2D {
         let (source_rect, dest_rect) = self.adjust_source_dest_rects(image_size, sx, sy, sw, sh, dx, dy, dw, dh);
 
         if !is_rect_valid(source_rect) || !is_rect_valid(dest_rect) {
-            return Err(IndexSize)
+            return Err(Error::IndexSize)
         }
 
         let smoothing_enabled = self.state.borrow().image_smoothing_enabled;
@@ -715,7 +714,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
         }
 
         if r < 0.0 {
-            return Err(IndexSize);
+            return Err(Error::IndexSize);
         }
 
         let msg = CanvasMsg::Canvas2d(
@@ -733,7 +732,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
             return Ok(());
         }
         if r < 0.0 {
-            return Err(IndexSize);
+            return Err(Error::IndexSize);
         }
 
         let msg = CanvasMsg::Canvas2d(
@@ -839,7 +838,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
     // https://html.spec.whatwg.org/multipage/#dom-context-2d-createimagedata
     fn CreateImageData(&self, sw: Finite<f64>, sh: Finite<f64>) -> Fallible<Root<ImageData>> {
         if *sw == 0.0 || *sh == 0.0 {
-            return Err(IndexSize)
+            return Err(Error::IndexSize)
         }
 
         let sw = cmp::max(1, sw.abs().to_u32().unwrap());
@@ -864,7 +863,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
         let mut sh = *sh;
 
         if sw == 0.0 || sh == 0.0 {
-            return Err(IndexSize)
+            return Err(Error::IndexSize)
         }
 
         if sw < 0.0 {
@@ -935,7 +934,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
                             x1: Finite<f64>, y1: Finite<f64>, r1: Finite<f64>)
                             -> Fallible<Root<CanvasGradient>> {
         if *r0 < 0. || *r1 < 0. {
-            return Err(IndexSize);
+            return Err(Error::IndexSize);
         }
 
         Ok(CanvasGradient::new(self.global.root().r(),
@@ -954,7 +953,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
                 // then throw an InvalidStateError exception
                 match self.fetch_image_data(&image_element) {
                     Some((data, size)) => (data, size),
-                    None => return Err(InvalidState),
+                    None => return Err(Error::InvalidState),
                 }
             },
             HTMLImageElementOrHTMLCanvasElementOrCanvasRenderingContext2D::eHTMLCanvasElement(canvas) => {
@@ -963,7 +962,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
 
                 match canvas.fetch_all_data() {
                     Some((data, size)) => (data, size),
-                    None => return Err(InvalidState),
+                    None => return Err(Error::InvalidState),
                 }
             },
             HTMLImageElementOrHTMLCanvasElementOrCanvasRenderingContext2D::eCanvasRenderingContext2D(context) => {
@@ -973,7 +972,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
 
                 match canvas.fetch_all_data() {
                     Some((data, size)) => (data, size),
-                    None => return Err(InvalidState),
+                    None => return Err(Error::InvalidState),
                 }
             },
         };
@@ -984,7 +983,7 @@ impl CanvasRenderingContext2DMethods for CanvasRenderingContext2D {
                                          image_size,
                                          rep));
         }
-        return Err(Syntax);
+        return Err(Error::Syntax);
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-context-2d-linewidth
diff --git a/components/script/dom/characterdata.rs b/components/script/dom/characterdata.rs
index 58f71d40d7c..01d6efac1e5 100644
--- a/components/script/dom/characterdata.rs
+++ b/components/script/dom/characterdata.rs
@@ -9,8 +9,7 @@ use dom::bindings::codegen::Bindings::CharacterDataBinding::CharacterDataMethods
 use dom::bindings::codegen::InheritTypes::NodeCast;
 use dom::bindings::codegen::InheritTypes::{CharacterDataDerived, ElementCast};
 use dom::bindings::codegen::UnionTypes::NodeOrString;
-use dom::bindings::error::Error::IndexSize;
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::js::{LayoutJS, Root};
 use dom::document::Document;
 use dom::element::Element;
@@ -69,7 +68,7 @@ impl CharacterDataMethods for CharacterData {
         let data_from_offset = match find_utf16_code_unit_offset(&data, offset) {
             Some(offset_bytes) => &data[offset_bytes..],
             // Step 2.
-            None => return Err(IndexSize)
+            None => return Err(Error::IndexSize)
         };
         let substring = match find_utf16_code_unit_offset(data_from_offset, count) {
             // Steps 3.
@@ -102,7 +101,7 @@ impl CharacterDataMethods for CharacterData {
             let (prefix, data_from_offset) = match find_utf16_code_unit_offset(&data, offset) {
                 Some(offset_bytes) => data.split_at(offset_bytes),
                 // Step 2.
-                None => return Err(IndexSize)
+                None => return Err(Error::IndexSize)
             };
             let suffix = match find_utf16_code_unit_offset(data_from_offset, count) {
                 // Steps 3.
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index c68924c3fd6..f2ca26a2cdb 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -25,9 +25,7 @@ use dom::bindings::codegen::InheritTypes::{HTMLAreaElementDerived, HTMLEmbedElem
 use dom::bindings::codegen::InheritTypes::{HTMLFormElementDerived, HTMLImageElementDerived};
 use dom::bindings::codegen::InheritTypes::{HTMLScriptElementDerived, HTMLTitleElementDerived};
 use dom::bindings::codegen::UnionTypes::NodeOrString;
-use dom::bindings::error::Error::HierarchyRequest;
-use dom::bindings::error::Error::{InvalidCharacter, NotSupported, Security};
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::RootedReference;
 use dom::bindings::js::{JS, LayoutJS, MutNullableHeap, Root};
@@ -1265,7 +1263,7 @@ impl DocumentMethods for Document {
     fn CreateElement(&self, mut local_name: DOMString) -> Fallible<Root<Element>> {
         if xml_name_type(&local_name) == InvalidXMLName {
             debug!("Not a valid element name");
-            return Err(InvalidCharacter);
+            return Err(Error::InvalidCharacter);
         }
         if self.is_html_document {
             local_name.make_ascii_lowercase();
@@ -1288,7 +1286,7 @@ impl DocumentMethods for Document {
     fn CreateAttribute(&self, local_name: DOMString) -> Fallible<Root<Attr>> {
         if xml_name_type(&local_name) == InvalidXMLName {
             debug!("Not a valid element name");
-            return Err(InvalidCharacter);
+            return Err(Error::InvalidCharacter);
         }
 
         let window = self.window.root();
@@ -1332,12 +1330,12 @@ impl DocumentMethods for Document {
             Fallible<Root<ProcessingInstruction>> {
         // Step 1.
         if xml_name_type(&target) == InvalidXMLName {
-            return Err(InvalidCharacter);
+            return Err(Error::InvalidCharacter);
         }
 
         // Step 2.
         if data.contains("?>") {
-            return Err(InvalidCharacter);
+            return Err(Error::InvalidCharacter);
         }
 
         // Step 3.
@@ -1348,7 +1346,7 @@ impl DocumentMethods for Document {
     fn ImportNode(&self, node: &Node, deep: bool) -> Fallible<Root<Node>> {
         // Step 1.
         if node.is_document() {
-            return Err(NotSupported);
+            return Err(Error::NotSupported);
         }
 
         // Step 2.
@@ -1364,7 +1362,7 @@ impl DocumentMethods for Document {
     fn AdoptNode(&self, node: &Node) -> Fallible<Root<Node>> {
         // Step 1.
         if node.is_document() {
-            return Err(NotSupported);
+            return Err(Error::NotSupported);
         }
 
         // Step 2.
@@ -1392,7 +1390,7 @@ impl DocumentMethods for Document {
                 KeyboardEvent::new_uninitialized(window.r()))),
             "messageevent" => Ok(EventCast::from_root(
                 MessageEvent::new_uninitialized(GlobalRef::Window(window.r())))),
-            _ => Err(NotSupported)
+            _ => Err(Error::NotSupported)
         }
     }
 
@@ -1535,14 +1533,14 @@ impl DocumentMethods for Document {
         // Step 1.
         let new_body = match new_body {
             Some(new_body) => new_body,
-            None => return Err(HierarchyRequest),
+            None => return Err(Error::HierarchyRequest),
         };
 
         let node = NodeCast::from_ref(new_body);
         match node.type_id() {
             NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLBodyElement)) |
             NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLFrameSetElement)) => {}
-            _ => return Err(HierarchyRequest)
+            _ => return Err(Error::HierarchyRequest)
         }
 
         // Step 2.
@@ -1561,7 +1559,7 @@ impl DocumentMethods for Document {
             },
 
             // Step 4.
-            (None, _) => return Err(HierarchyRequest),
+            (None, _) => return Err(Error::HierarchyRequest),
 
             // Step 5.
             (Some(ref root), &None) => {
@@ -1730,7 +1728,7 @@ impl DocumentMethods for Document {
         //TODO: return empty string for cookie-averse Document
         let url = self.url();
         if !is_scheme_host_port_tuple(&url) {
-            return Err(Security);
+            return Err(Error::Security);
         }
         let window = self.window.root();
         let (tx, rx) = ipc::channel().unwrap();
@@ -1744,7 +1742,7 @@ impl DocumentMethods for Document {
         //TODO: ignore for cookie-averse Document
         let url = self.url();
         if !is_scheme_host_port_tuple(url) {
-            return Err(Security);
+            return Err(Error::Security);
         }
         let window = self.window.root();
         let _ = window.r().resource_task().send(SetCookiesForUrl((*url).clone(), cookie, NonHTTP));
diff --git a/components/script/dom/domtokenlist.rs b/components/script/dom/domtokenlist.rs
index 95c743664f9..e13c1448d70 100644
--- a/components/script/dom/domtokenlist.rs
+++ b/components/script/dom/domtokenlist.rs
@@ -5,8 +5,7 @@
 use dom::attr::Attr;
 use dom::bindings::codegen::Bindings::DOMTokenListBinding;
 use dom::bindings::codegen::Bindings::DOMTokenListBinding::DOMTokenListMethods;
-use dom::bindings::error::Error::{InvalidCharacter, Syntax};
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, Root};
 use dom::bindings::utils::{Reflector, reflect_dom_object};
@@ -46,8 +45,8 @@ impl DOMTokenList {
 
     fn check_token_exceptions(&self, token: &str) -> Fallible<Atom> {
         match token {
-            "" => Err(Syntax),
-            slice if slice.find(HTML_SPACE_CHARACTERS).is_some() => Err(InvalidCharacter),
+            "" => Err(Error::Syntax),
+            slice if slice.find(HTML_SPACE_CHARACTERS).is_some() => Err(Error::InvalidCharacter),
             slice => Ok(Atom::from_slice(slice))
         }
     }
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index dd4bff543e0..24d10497f01 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -28,9 +28,7 @@ use dom::bindings::codegen::InheritTypes::{HTMLTableRowElementCast, HTMLTableSec
 use dom::bindings::codegen::InheritTypes::{HTMLTemplateElementCast, HTMLTextAreaElementCast};
 use dom::bindings::codegen::InheritTypes::{NodeCast, TextCast};
 use dom::bindings::codegen::UnionTypes::NodeOrString;
-use dom::bindings::error::Error::NoModificationAllowed;
-use dom::bindings::error::Error::{InvalidCharacter, Syntax};
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::js::{JS, LayoutJS, MutNullableHeap};
 use dom::bindings::js::{Root, RootedReference};
 use dom::bindings::utils::XMLName::InvalidXMLName;
@@ -909,7 +907,7 @@ impl Element {
     pub fn set_custom_attribute(&self, name: DOMString, value: DOMString) -> ErrorResult {
         // Step 1.
         match xml_name_type(&name) {
-            InvalidXMLName => return Err(InvalidCharacter),
+            InvalidXMLName => return Err(Error::InvalidCharacter),
             _ => {}
         }
 
@@ -1174,7 +1172,7 @@ impl ElementMethods for Element {
                     value: DOMString) -> ErrorResult {
         // Step 1.
         if xml_name_type(&name) == InvalidXMLName {
-            return Err(InvalidCharacter);
+            return Err(Error::InvalidCharacter);
         }
 
         // Step 2.
@@ -1341,7 +1339,7 @@ impl ElementMethods for Element {
 
         let parent = match context_parent.r().type_id() {
             // Step 3.
-            NodeTypeId::Document => return Err(NoModificationAllowed),
+            NodeTypeId::Document => return Err(Error::NoModificationAllowed),
 
             // Step 4.
             NodeTypeId::DocumentFragment => {
@@ -1440,7 +1438,7 @@ impl ElementMethods for Element {
     // https://dom.spec.whatwg.org/#dom-element-matches
     fn Matches(&self, selectors: DOMString) -> Fallible<bool> {
         match parse_author_origin_selector_list_from_str(&selectors) {
-            Err(()) => Err(Syntax),
+            Err(()) => Err(Error::Syntax),
             Ok(ref selectors) => {
                 Ok(matches(selectors, &Root::from_ref(self), None))
             }
@@ -1450,7 +1448,7 @@ impl ElementMethods for Element {
     // https://dom.spec.whatwg.org/#dom-element-closest
     fn Closest(&self, selectors: DOMString) -> Fallible<Option<Root<Element>>> {
         match parse_author_origin_selector_list_from_str(&selectors) {
-            Err(()) => Err(Syntax),
+            Err(()) => Err(Error::Syntax),
             Ok(ref selectors) => {
                 let root = NodeCast::from_ref(self);
                 for element in root.inclusive_ancestors() {
diff --git a/components/script/dom/eventtarget.rs b/components/script/dom/eventtarget.rs
index 0a7f8a151de..86a3d14ea1b 100644
--- a/components/script/dom/eventtarget.rs
+++ b/components/script/dom/eventtarget.rs
@@ -8,8 +8,7 @@ use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::Bindings::EventListenerBinding::EventListener;
 use dom::bindings::codegen::Bindings::EventTargetBinding::EventTargetMethods;
 use dom::bindings::conversions::get_dom_class;
-use dom::bindings::error::Error::InvalidState;
-use dom::bindings::error::{Fallible, report_pending_exception};
+use dom::bindings::error::{Error, Fallible, report_pending_exception};
 use dom::bindings::utils::{Reflectable, Reflector};
 use dom::event::Event;
 use dom::eventdispatcher::dispatch_event;
@@ -333,7 +332,7 @@ impl EventTargetMethods for EventTarget {
     // https://dom.spec.whatwg.org/#dom-eventtarget-dispatchevent
     fn DispatchEvent(&self, event: &Event) -> Fallible<bool> {
         if event.dispatching() || !event.initialized() {
-            return Err(InvalidState);
+            return Err(Error::InvalidState);
         }
         event.set_trusted(false);
         Ok(self.dispatch_event(event))
diff --git a/components/script/dom/filereader.rs b/components/script/dom/filereader.rs
index 2169edebb03..219f1a2c1de 100644
--- a/components/script/dom/filereader.rs
+++ b/components/script/dom/filereader.rs
@@ -6,8 +6,7 @@ use dom::bindings::codegen::Bindings::BlobBinding::BlobMethods;
 use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::Bindings::FileReaderBinding::{self, FileReaderConstants, FileReaderMethods};
 use dom::bindings::codegen::InheritTypes::{EventCast, EventTargetCast};
-use dom::bindings::error::Error::InvalidState;
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::{GlobalField, GlobalRef};
 use dom::bindings::js::{JS, MutNullableHeap, Root};
 use dom::bindings::refcounted::Trusted;
@@ -341,7 +340,7 @@ impl FileReader {
         let global = root.r();
         // Step 1
         if self.ready_state.get() == FileReaderReadyState::Loading {
-            return Err(InvalidState);
+            return Err(Error::InvalidState);
         }
         // Step 2
         if blob.IsClosed() {
diff --git a/components/script/dom/htmlelement.rs b/components/script/dom/htmlelement.rs
index ba44495e508..395b1b83c3b 100644
--- a/components/script/dom/htmlelement.rs
+++ b/components/script/dom/htmlelement.rs
@@ -12,8 +12,7 @@ use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::InheritTypes::{ElementCast, HTMLFrameSetElementDerived};
 use dom::bindings::codegen::InheritTypes::{EventTargetCast, HTMLInputElementCast, NodeCast};
 use dom::bindings::codegen::InheritTypes::{HTMLBodyElementDerived, HTMLElementDerived, HTMLHtmlElementDerived};
-use dom::bindings::error::Error::Syntax;
-use dom::bindings::error::ErrorResult;
+use dom::bindings::error::{Error, ErrorResult};
 use dom::bindings::js::{JS, MutNullableHeap, Root};
 use dom::bindings::utils::Reflectable;
 use dom::cssstyledeclaration::{CSSModificationAccess, CSSStyleDeclaration};
@@ -289,7 +288,7 @@ impl HTMLElement {
         if name.chars()
                .skip_while(|&ch| ch != '\u{2d}')
                .nth(1).map_or(false, |ch| ch >= 'a' && ch <= 'z') {
-            return Err(Syntax);
+            return Err(Error::Syntax);
         }
         let element = ElementCast::from_ref(self);
         element.set_custom_attribute(to_snake_case(name), value)
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 8e0016f4bb0..f9b74e27bce 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -10,8 +10,7 @@ use dom::bindings::codegen::InheritTypes::HTMLIFrameElementDerived;
 use dom::bindings::codegen::InheritTypes::{ElementCast, EventCast, NodeCast};
 use dom::bindings::codegen::InheritTypes::{EventTargetCast, HTMLElementCast};
 use dom::bindings::conversions::ToJSValConvertible;
-use dom::bindings::error::Error::NotSupported;
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{Root};
 use dom::bindings::utils::Reflectable;
@@ -232,7 +231,7 @@ pub fn Navigate(iframe: &HTMLIFrameElement, direction: NavigationDirection) -> F
         Ok(())
     } else {
         debug!("this frame is not mozbrowser (or experimental_enabled is false)");
-        Err(NotSupported)
+        Err(Error::NotSupported)
     }
 }
 
@@ -329,12 +328,12 @@ impl HTMLIFrameElementMethods for HTMLIFrameElement {
 
     // https://developer.mozilla.org/en-US/docs/Web/API/HTMLIFrameElement/reload
     fn Reload(&self, _hardReload: bool) -> Fallible<()> {
-        Err(NotSupported)
+        Err(Error::NotSupported)
     }
 
     // https://developer.mozilla.org/en-US/docs/Web/API/HTMLIFrameElement/stop
     fn Stop(&self) -> Fallible<()> {
-        Err(NotSupported)
+        Err(Error::NotSupported)
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-dim-width
diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 7f131baf52f..48df7dbf490 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -25,8 +25,7 @@ use dom::bindings::codegen::InheritTypes::{HTMLOptGroupElementDerived, NodeBase,
 use dom::bindings::codegen::InheritTypes::{ProcessingInstructionCast, TextCast, TextDerived};
 use dom::bindings::codegen::UnionTypes::NodeOrString;
 use dom::bindings::conversions;
-use dom::bindings::error::Error::{HierarchyRequest, NotFound, Syntax};
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::Root;
 use dom::bindings::js::RootedReference;
@@ -807,7 +806,7 @@ impl Node {
         // Step 1.
         match parse_author_origin_selector_list_from_str(&selectors) {
             // Step 2.
-            Err(()) => Err(Syntax),
+            Err(()) => Err(Error::Syntax),
             // Step 3.
             Ok(ref selectors) => {
                 Ok(self.traverse_preorder().filter_map(ElementCast::to_root).find(|element| {
@@ -827,7 +826,7 @@ impl Node {
         // Step 1.
         match parse_author_origin_selector_list_from_str(&selectors) {
             // Step 2.
-            Err(()) => Err(Syntax),
+            Err(()) => Err(Error::Syntax),
             // Step 3.
             Ok(selectors) => {
                 Ok(QuerySelectorIterator::new(self.traverse_preorder(), selectors))
@@ -1432,18 +1431,18 @@ impl Node {
             NodeTypeId::Document |
             NodeTypeId::DocumentFragment |
             NodeTypeId::Element(..) => (),
-            _ => return Err(HierarchyRequest)
+            _ => return Err(Error::HierarchyRequest)
         }
 
         // Step 2.
         if node.is_inclusive_ancestor_of(parent) {
-            return Err(HierarchyRequest);
+            return Err(Error::HierarchyRequest);
         }
 
         // Step 3.
         if let Some(child) = child {
             if !parent.is_parent_of(child) {
-                return Err(NotFound);
+                return Err(Error::NotFound);
             }
         }
 
@@ -1451,19 +1450,19 @@ impl Node {
         match node.type_id() {
             NodeTypeId::CharacterData(CharacterDataTypeId::Text) => {
                 if parent.is_document() {
-                    return Err(HierarchyRequest);
+                    return Err(Error::HierarchyRequest);
                 }
             },
             NodeTypeId::DocumentType => {
                 if !parent.is_document() {
-                    return Err(HierarchyRequest);
+                    return Err(Error::HierarchyRequest);
                 }
             },
             NodeTypeId::DocumentFragment |
             NodeTypeId::Element(_) |
             NodeTypeId::CharacterData(CharacterDataTypeId::ProcessingInstruction) |
             NodeTypeId::CharacterData(CharacterDataTypeId::Comment) => (),
-            NodeTypeId::Document => return Err(HierarchyRequest)
+            NodeTypeId::Document => return Err(Error::HierarchyRequest)
         }
 
         // Step 6.
@@ -1475,35 +1474,35 @@ impl Node {
                     if node.children()
                            .any(|c| c.r().is_text())
                     {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                     match node.child_elements().count() {
                         0 => (),
                         // Step 6.1.2
                         1 => {
                             if !parent.child_elements().is_empty() {
-                                return Err(HierarchyRequest);
+                                return Err(Error::HierarchyRequest);
                             }
                             if let Some(child) = child {
                                 if child.inclusively_following_siblings()
                                     .any(|child| child.r().is_doctype()) {
-                                        return Err(HierarchyRequest);
+                                        return Err(Error::HierarchyRequest);
                                 }
                             }
                         },
                         // Step 6.1.1(a)
-                        _ => return Err(HierarchyRequest),
+                        _ => return Err(Error::HierarchyRequest),
                     }
                 },
                 // Step 6.2
                 NodeTypeId::Element(_) => {
                     if !parent.child_elements().is_empty() {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                     if let Some(ref child) = child {
                         if child.inclusively_following_siblings()
                             .any(|child| child.r().is_doctype()) {
-                                return Err(HierarchyRequest);
+                                return Err(Error::HierarchyRequest);
                         }
                     }
                 },
@@ -1512,7 +1511,7 @@ impl Node {
                     if parent.children()
                              .any(|c| c.r().is_doctype())
                     {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                     match child {
                         Some(child) => {
@@ -1520,12 +1519,12 @@ impl Node {
                                      .take_while(|c| c.r() != child)
                                      .any(|c| c.r().is_element())
                             {
-                                return Err(HierarchyRequest);
+                                return Err(Error::HierarchyRequest);
                             }
                         },
                         None => {
                             if !parent.child_elements().is_empty() {
-                                return Err(HierarchyRequest);
+                                return Err(Error::HierarchyRequest);
                             }
                         },
                     }
@@ -1647,8 +1646,8 @@ impl Node {
     fn pre_remove(child: &Node, parent: &Node) -> Fallible<Root<Node>> {
         // Step 1.
         match child.GetParentNode() {
-            Some(ref node) if node.r() != parent => return Err(NotFound),
-            None => return Err(NotFound),
+            Some(ref node) if node.r() != parent => return Err(Error::NotFound),
+            None => return Err(Error::NotFound),
             _ => ()
         }
 
@@ -2070,25 +2069,25 @@ impl NodeMethods for Node {
             NodeTypeId::Document |
             NodeTypeId::DocumentFragment |
             NodeTypeId::Element(..) => (),
-            _ => return Err(HierarchyRequest)
+            _ => return Err(Error::HierarchyRequest)
         }
 
         // Step 2.
         if node.is_inclusive_ancestor_of(self) {
-            return Err(HierarchyRequest);
+            return Err(Error::HierarchyRequest);
         }
 
         // Step 3.
         if !self.is_parent_of(child) {
-            return Err(NotFound);
+            return Err(Error::NotFound);
         }
 
         // Step 4-5.
         match node.type_id() {
             NodeTypeId::CharacterData(CharacterDataTypeId::Text) if self.is_document() =>
-                return Err(HierarchyRequest),
-            NodeTypeId::DocumentType if !self.is_document() => return Err(HierarchyRequest),
-            NodeTypeId::Document => return Err(HierarchyRequest),
+                return Err(Error::HierarchyRequest),
+            NodeTypeId::DocumentType if !self.is_document() => return Err(Error::HierarchyRequest),
+            NodeTypeId::Document => return Err(Error::HierarchyRequest),
             _ => ()
         }
 
@@ -2101,7 +2100,7 @@ impl NodeMethods for Node {
                     if node.children()
                            .any(|c| c.is_text())
                     {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                     match node.child_elements().count() {
                         0 => (),
@@ -2109,27 +2108,27 @@ impl NodeMethods for Node {
                         1 => {
                             if self.child_elements()
                                    .any(|c| NodeCast::from_ref(c.r()) != child) {
-                                return Err(HierarchyRequest);
+                                return Err(Error::HierarchyRequest);
                             }
                             if child.following_siblings()
                                     .any(|child| child.is_doctype()) {
-                                return Err(HierarchyRequest);
+                                return Err(Error::HierarchyRequest);
                             }
                         },
                         // Step 6.1.1(a)
-                        _ => return Err(HierarchyRequest)
+                        _ => return Err(Error::HierarchyRequest)
                     }
                 },
                 // Step 6.2
                 NodeTypeId::Element(..) => {
                     if self.child_elements()
                            .any(|c| NodeCast::from_ref(c.r()) != child) {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                     if child.following_siblings()
                             .any(|child| child.is_doctype())
                     {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                 },
                 // Step 6.3
@@ -2138,13 +2137,13 @@ impl NodeMethods for Node {
                            .any(|c| c.is_doctype() &&
                                 c.r() != child)
                     {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                     if self.children()
                            .take_while(|c| c.r() != child)
                            .any(|c| c.is_element())
                     {
-                        return Err(HierarchyRequest);
+                        return Err(Error::HierarchyRequest);
                     }
                 },
                 NodeTypeId::CharacterData(..) => (),
diff --git a/components/script/dom/range.rs b/components/script/dom/range.rs
index 3373d129169..ea85eeb6033 100644
--- a/components/script/dom/range.rs
+++ b/components/script/dom/range.rs
@@ -11,7 +11,6 @@ use dom::bindings::codegen::Bindings::RangeBinding::{self, RangeConstants};
 use dom::bindings::codegen::Bindings::TextBinding::TextMethods;
 use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::InheritTypes::{CharacterDataCast, NodeCast, TextCast, TextDerived};
-use dom::bindings::error::Error::HierarchyRequest;
 use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, Root, RootedReference};
@@ -117,7 +116,7 @@ impl Range {
 
         // Step 12.
         if contained_children.iter().any(|n| n.is_doctype()) {
-            return Err(HierarchyRequest);
+            return Err(Error::HierarchyRequest);
         }
 
         Ok((first_contained_child, last_contained_child, contained_children))
@@ -597,7 +596,7 @@ impl RangeMethods for Range {
         match start_node.type_id() {
             // Handled under step 2.
             NodeTypeId::CharacterData(CharacterDataTypeId::Text) => (),
-            NodeTypeId::CharacterData(_) => return Err(HierarchyRequest),
+            NodeTypeId::CharacterData(_) => return Err(Error::HierarchyRequest),
             _ => ()
         }
 
@@ -608,7 +607,7 @@ impl RangeMethods for Range {
                 let parent = match start_node.GetParentNode() {
                     Some(parent) => parent,
                     // Step 1.
-                    None => return Err(HierarchyRequest)
+                    None => return Err(Error::HierarchyRequest)
                 };
                 // Step 5.
                 (Some(Root::from_ref(start_node.r())), parent)
diff --git a/components/script/dom/textencoder.rs b/components/script/dom/textencoder.rs
index 17d5e0aeb60..913b7c4fe86 100644
--- a/components/script/dom/textencoder.rs
+++ b/components/script/dom/textencoder.rs
@@ -4,8 +4,7 @@
 
 use dom::bindings::codegen::Bindings::TextEncoderBinding;
 use dom::bindings::codegen::Bindings::TextEncoderBinding::TextEncoderMethods;
-use dom::bindings::error::Error::Range;
-use dom::bindings::error::Fallible;
+use dom::bindings::error::{Error, Fallible};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::Root;
 use dom::bindings::str::USVString;
@@ -50,7 +49,7 @@ impl TextEncoder {
             Some(enc) => enc,
             None => {
                 debug!("Encoding Label Not Supported");
-                return Err(Range("The given encoding is not supported.".to_owned()))
+                return Err(Error::Range("The given encoding is not supported.".to_owned()))
             }
         };
 
@@ -60,7 +59,7 @@ impl TextEncoder {
             }
             _ => {
                 debug!("Encoding Not UTF");
-                Err(Range("The encoding must be utf-8, utf-16le, or utf-16be.".to_owned()))
+                Err(Error::Range("The encoding must be utf-8, utf-16le, or utf-16be.".to_owned()))
             }
         }
     }
diff --git a/components/script/dom/websocket.rs b/components/script/dom/websocket.rs
index b90cd53ff06..84e78bc8832 100644
--- a/components/script/dom/websocket.rs
+++ b/components/script/dom/websocket.rs
@@ -9,7 +9,6 @@ use dom::bindings::codegen::Bindings::WebSocketBinding::{BinaryType, WebSocketMe
 use dom::bindings::codegen::InheritTypes::EventCast;
 use dom::bindings::codegen::InheritTypes::EventTargetCast;
 use dom::bindings::conversions::ToJSValConvertible;
-use dom::bindings::error::Error::{InvalidAccess, Syntax};
 use dom::bindings::error::{Error, Fallible};
 use dom::bindings::global::{GlobalField, GlobalRef};
 use dom::bindings::js::Root;
@@ -146,15 +145,15 @@ impl WebSocket {
             // https://tools.ietf.org/html/rfc6455#section-4.1
             // Handshake requirements, step 10
             if protocol.is_empty() {
-                return Err(Syntax);
+                return Err(Error::Syntax);
             }
 
             if protocols[i + 1..].iter().any(|p| p == protocol) {
-                return Err(Syntax);
+                return Err(Error::Syntax);
             }
 
             if protocol.chars().any(|c| c < '\u{0021}' || c > '\u{007E}') {
-                return Err(Syntax);
+                return Err(Error::Syntax);
             }
         }
 
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 21b26a529b2..61a18274ec9 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -12,8 +12,7 @@ use dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use dom::bindings::codegen::Bindings::WindowBinding::{ScrollBehavior, ScrollToOptions};
 use dom::bindings::codegen::Bindings::WindowBinding::{self, FrameRequestCallback, WindowMethods};
 use dom::bindings::codegen::InheritTypes::{ElementCast, EventTargetCast, NodeCast, WindowDerived};
-use dom::bindings::error::Error::InvalidCharacter;
-use dom::bindings::error::{Fallible, report_pending_exception};
+use dom::bindings::error::{Error, Fallible, report_pending_exception};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::global::global_object_for_js_object;
 use dom::bindings::js::RootedReference;
@@ -298,7 +297,7 @@ pub fn base64_btoa(input: DOMString) -> Fallible<DOMString> {
     //  the method's first argument contains any character whose code point
     //  is greater than U+00FF."
     if input.chars().any(|c: char| c > '\u{FF}') {
-        Err(InvalidCharacter)
+        Err(Error::InvalidCharacter)
     } else {
         // "Otherwise, the user agent must convert that argument to a
         //  sequence of octets whose nth octet is the eight-bit
@@ -340,7 +339,7 @@ pub fn base64_atob(input: DOMString) -> Fallible<DOMString> {
     // "If the length of input divides by 4 leaving a remainder of 1,
     //  throw an InvalidCharacterError exception and abort these steps."
     if input.len() % 4 == 1 {
-        return Err(InvalidCharacter)
+        return Err(Error::InvalidCharacter)
     }
 
     // "If input contains a character that is not in the following list of
@@ -351,12 +350,12 @@ pub fn base64_atob(input: DOMString) -> Fallible<DOMString> {
     //  U+002F SOLIDUS (/)
     //  Alphanumeric ASCII characters"
     if input.chars().any(|c| c != '+' && c != '/' && !c.is_alphanumeric()) {
-        return Err(InvalidCharacter)
+        return Err(Error::InvalidCharacter)
     }
 
     match input.from_base64() {
         Ok(data) => Ok(data.iter().map(|&b| b as char).collect::<String>()),
-        Err(..) => Err(InvalidCharacter)
+        Err(..) => Err(Error::InvalidCharacter)
     }
 }
 
diff --git a/components/script/dom/worker.rs b/components/script/dom/worker.rs
index 5a6d264f714..5d10c632c8e 100644
--- a/components/script/dom/worker.rs
+++ b/components/script/dom/worker.rs
@@ -7,8 +7,7 @@ use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::Bindings::WorkerBinding;
 use dom::bindings::codegen::Bindings::WorkerBinding::WorkerMethods;
 use dom::bindings::codegen::InheritTypes::{EventCast, EventTargetCast};
-use dom::bindings::error::Error::Syntax;
-use dom::bindings::error::{ErrorResult, Fallible};
+use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::{GlobalField, GlobalRef};
 use dom::bindings::js::Root;
 use dom::bindings::refcounted::Trusted;
@@ -68,7 +67,7 @@ impl Worker {
         // Step 2-4.
         let worker_url = match UrlParser::new().base_url(&global.get_url()).parse(&script_url) {
             Ok(url) => url,
-            Err(_) => return Err(Syntax),
+            Err(_) => return Err(Error::Syntax),
         };
 
         let resource_task = global.resource_task();
diff --git a/components/script/dom/workerglobalscope.rs b/components/script/dom/workerglobalscope.rs
index 881a6ef3c2f..bd01fce1658 100644
--- a/components/script/dom/workerglobalscope.rs
+++ b/components/script/dom/workerglobalscope.rs
@@ -6,8 +6,7 @@ use devtools_traits::{DevtoolScriptControlMsg, ScriptToDevtoolsControlMsg};
 use dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use dom::bindings::codegen::Bindings::WorkerGlobalScopeBinding::WorkerGlobalScopeMethods;
 use dom::bindings::codegen::InheritTypes::DedicatedWorkerGlobalScopeCast;
-use dom::bindings::error::Error::{JSFailed, Network, Syntax};
-use dom::bindings::error::{ErrorResult, Fallible, report_pending_exception};
+use dom::bindings::error::{Error, ErrorResult, Fallible, report_pending_exception};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, MutNullableHeap, Root};
 use dom::bindings::utils::Reflectable;
@@ -177,13 +176,13 @@ impl WorkerGlobalScopeMethods for WorkerGlobalScope {
                                       .parse(&url);
             match url {
                 Ok(url) => urls.push(url),
-                Err(_) => return Err(Syntax),
+                Err(_) => return Err(Error::Syntax),
             };
         }
 
         for url in urls {
             let (url, source) = match load_whole_resource(&self.resource_task, url) {
-                Err(_) => return Err(Network),
+                Err(_) => return Err(Error::Network),
                 Ok((metadata, bytes)) => {
                     (metadata.final_url, String::from_utf8(bytes).unwrap())
                 }
@@ -194,7 +193,7 @@ impl WorkerGlobalScopeMethods for WorkerGlobalScope {
                 Ok(_) => (),
                 Err(_) => {
                     println!("evaluate_script failed");
-                    return Err(JSFailed);
+                    return Err(Error::JSFailed);
                 }
             }
         }
diff --git a/components/script/dom/xmlhttprequest.rs b/components/script/dom/xmlhttprequest.rs
index ccff93ad5be..04756a93278 100644
--- a/components/script/dom/xmlhttprequest.rs
+++ b/components/script/dom/xmlhttprequest.rs
@@ -14,8 +14,6 @@ use dom::bindings::codegen::InheritTypes::{EventCast, EventTargetCast, XMLHttpRe
 use dom::bindings::codegen::UnionTypes::StringOrURLSearchParams;
 use dom::bindings::codegen::UnionTypes::StringOrURLSearchParams::{eString, eURLSearchParams};
 use dom::bindings::conversions::ToJSValConvertible;
-use dom::bindings::error::Error::{Abort, Network, Security, Syntax, Timeout};
-use dom::bindings::error::Error::{InvalidAccess, InvalidState};
 use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::{GlobalField, GlobalRef, GlobalRoot};
 use dom::bindings::js::Root;
@@ -94,7 +92,7 @@ pub enum XHRProgress {
     Loading(GenerationId, ByteString),
     /// Loading is done
     Done(GenerationId),
-    /// There was an error (only Abort, Timeout or Network is used)
+    /// There was an error (only Error::Abort, Error::Timeout or Error::Network is used)
     Errored(GenerationId, Error),
 }
 
@@ -209,8 +207,8 @@ impl XMLHttpRequest {
                 if response.network_error {
                     let mut context = self.xhr.lock().unwrap();
                     let xhr = context.xhr.root();
-                    xhr.r().process_partial_response(XHRProgress::Errored(context.gen_id, Network));
-                    *context.sync_status.borrow_mut() = Some(Err(Network));
+                    xhr.r().process_partial_response(XHRProgress::Errored(context.gen_id, Error::Network));
+                    *context.sync_status.borrow_mut() = Some(Err(Error::Network));
                     return;
                 }
 
@@ -315,12 +313,12 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
         // Step 2
         match maybe_method {
             // Step 4
-            Some(Method::Connect) | Some(Method::Trace) => Err(Security),
-            Some(Method::Extension(ref t)) if &**t == "TRACK" => Err(Security),
+            Some(Method::Connect) | Some(Method::Trace) => Err(Error::Security),
+            Some(Method::Extension(ref t)) if &**t == "TRACK" => Err(Error::Security),
             Some(parsed_method) => {
                 // Step 3
                 if !method.is_token() {
-                    return Err(Syntax)
+                    return Err(Error::Syntax)
                 }
 
                 *self.request_method.borrow_mut() = parsed_method;
@@ -329,13 +327,13 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
                 let base = self.global.root().r().get_url();
                 let parsed_url = match UrlParser::new().base_url(&base).parse(&url) {
                     Ok(parsed) => parsed,
-                    Err(_) => return Err(Syntax) // Step 7
+                    Err(_) => return Err(Error::Syntax) // Step 7
                 };
                 // XXXManishearth Do some handling of username/passwords
                 if self.sync.get() {
                     // FIXME: This should only happen if the global environment is a document environment
                     if self.timeout.get() != 0 || self.with_credentials.get() || self.response_type.get() != _empty {
-                        return Err(InvalidAccess)
+                        return Err(Error::InvalidAccess)
                     }
                 }
                 // abort existing requests
@@ -356,7 +354,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
             },
             // This includes cases where as_str() returns None, and when is_token() returns false,
             // both of which indicate invalid extension method names
-            _ => Err(Syntax), // Step 3
+            _ => Err(Error::Syntax), // Step 3
         }
     }
 
@@ -370,10 +368,10 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
     // https://xhr.spec.whatwg.org/#the-setrequestheader()-method
     fn SetRequestHeader(&self, name: ByteString, mut value: ByteString) -> ErrorResult {
         if self.ready_state.get() != XMLHttpRequestState::Opened || self.send_flag.get() {
-            return Err(InvalidState); // Step 1, 2
+            return Err(Error::InvalidState); // Step 1, 2
         }
         if !name.is_token() || !value.is_field_value() {
-            return Err(Syntax); // Step 3, 4
+            return Err(Error::Syntax); // Step 3, 4
         }
         let name_lower = name.to_lower();
         let name_str = match name_lower.as_str() {
@@ -393,7 +391,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
                     _ => s
                 }
             },
-            None => return Err(Syntax)
+            None => return Err(Error::Syntax)
         };
 
         debug!("SetRequestHeader: name={:?}, value={:?}", name.as_str(), value.as_str());
@@ -426,7 +424,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
     fn SetTimeout(&self, timeout: u32) -> ErrorResult {
         if self.sync.get() {
             // FIXME: Not valid for a worker environment
-            Err(InvalidAccess)
+            Err(Error::InvalidAccess)
         } else {
             self.timeout.set(timeout);
             if self.send_flag.get() {
@@ -456,10 +454,10 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
         match self.ready_state.get() {
             XMLHttpRequestState::HeadersReceived |
             XMLHttpRequestState::Loading |
-            XMLHttpRequestState::Done => Err(InvalidState),
-            _ if self.send_flag.get() => Err(InvalidState),
+            XMLHttpRequestState::Done => Err(Error::InvalidState),
+            _ if self.send_flag.get() => Err(Error::InvalidState),
             _ => match self.global.root() {
-                GlobalRoot::Window(_) if self.sync.get() => Err(InvalidAccess),
+                GlobalRoot::Window(_) if self.sync.get() => Err(Error::InvalidAccess),
                 _ => {
                     self.with_credentials.set(with_credentials);
                     Ok(())
@@ -476,7 +474,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
     // https://xhr.spec.whatwg.org/#the-send()-method
     fn Send(&self, data: Option<SendParam>) -> ErrorResult {
         if self.ready_state.get() != XMLHttpRequestState::Opened || self.send_flag.get() {
-            return Err(InvalidState); // Step 1, 2
+            return Err(Error::InvalidState); // Step 1, 2
         }
 
         let data = match *self.request_method.borrow() {
@@ -613,7 +611,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
            state == XMLHttpRequestState::HeadersReceived ||
            state == XMLHttpRequestState::Loading {
             let gen_id = self.generation_id.get();
-            self.process_partial_response(XHRProgress::Errored(gen_id, Abort));
+            self.process_partial_response(XHRProgress::Errored(gen_id, Error::Abort));
             // If open was called in one of the handlers invoked by the
             // above call then we should terminate the abort sequence
             if self.generation_id.get() != gen_id {
@@ -665,8 +663,8 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
             _ => {}
         }
         match self.ready_state.get() {
-            XMLHttpRequestState::Loading | XMLHttpRequestState::Done => Err(InvalidState),
-            _ if self.sync.get() => Err(InvalidAccess),
+            XMLHttpRequestState::Loading | XMLHttpRequestState::Done => Err(Error::InvalidState),
+            _ if self.sync.get() => Err(Error::InvalidAccess),
             _ => {
                 self.response_type.set(response_type);
                 Ok(())
@@ -720,7 +718,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
                     _ => Ok("".to_owned())
                 }
             },
-            _ => Err(InvalidState)
+            _ => Err(Error::InvalidState)
         }
     }
 
@@ -763,8 +761,8 @@ impl XMLHttpRequest {
             match metadata.headers {
                 Some(ref h) if allow_cross_origin_request(req, h) => {},
                 _ => {
-                    self.process_partial_response(XHRProgress::Errored(gen_id, Network));
-                    return Err(Network);
+                    self.process_partial_response(XHRProgress::Errored(gen_id, Error::Network));
+                    return Err(Error::Network);
                 }
             }
         }
@@ -788,8 +786,8 @@ impl XMLHttpRequest {
                 Ok(())
             },
             Err(_) => {
-                self.process_partial_response(XHRProgress::Errored(gen_id, Network));
-                Err(Network)
+                self.process_partial_response(XHRProgress::Errored(gen_id, Error::Network));
+                Err(Error::Network)
             }
         }
     }
@@ -892,8 +890,8 @@ impl XMLHttpRequest {
                 return_if_fetch_was_terminated!();
 
                 let errormsg = match e {
-                    Abort => "abort",
-                    Timeout => "timeout",
+                    Error::Abort => "abort",
+                    Error::Timeout => "timeout",
                     _ => "error",
                 };
 
@@ -968,7 +966,7 @@ impl XMLHttpRequest {
                 let this = *self;
                 let xhr = this.xhr.root();
                 if xhr.r().ready_state.get() != XMLHttpRequestState::Done {
-                    xhr.r().process_partial_response(XHRProgress::Errored(this.gen_id, Timeout));
+                    xhr.r().process_partial_response(XHRProgress::Errored(this.gen_id, Error::Timeout));
                 }
             }
         }
@@ -1068,8 +1066,8 @@ impl XMLHttpRequest {
             Err(_) => {
                 // Happens in case of cross-origin non-http URIs
                 self.process_partial_response(XHRProgress::Errored(
-                    self.generation_id.get(), Network));
-                return Err(Network);
+                    self.generation_id.get(), Error::Network));
+                return Err(Error::Network);
             }
             Ok(req) => req,
         };