auto merge of #1664 : recrack/servo/object-element, r=jdm

Support for #1636

Now, we can see eyes in acid2.html :)

11 files changed, 161 insertions, 20 deletions

diff --git a/src/components/main/layout/construct.rs b/src/components/main/layout/construct.rs
index 293ba995da3..98d33db8d26 100644
--- a/src/components/main/layout/construct.rs
+++ b/src/components/main/layout/construct.rs
@@ -34,14 +34,19 @@ use layout::util::{LayoutDataAccess, OpaqueNode};
 use layout::wrapper::{PostorderNodeMutTraversal, TLayoutNode, ThreadSafeLayoutNode};
 
 use gfx::font_context::FontContext;
-use script::dom::element::{HTMLIframeElementTypeId, HTMLImageElementTypeId};
+use script::dom::element::{HTMLIframeElementTypeId, HTMLImageElementTypeId, HTMLObjectElementTypeId};
 use script::dom::node::{CommentNodeTypeId, DoctypeNodeTypeId, DocumentFragmentNodeTypeId};
 use script::dom::node::{DocumentNodeTypeId, ElementNodeTypeId, ProcessingInstructionNodeTypeId};
 use script::dom::node::{TextNodeTypeId};
 use style::computed_values::{display, position, float, white_space};
 use style::ComputedValues;
+use servo_util::namespace;
+use servo_util::url::parse_url;
+use servo_util::url::is_image_data;
 
+use extra::url::Url;
 use extra::arc::Arc;
+
 use std::cell::RefCell;
 use std::util;
 use std::num::Zero;
@@ -220,16 +225,20 @@ pub struct FlowConstructor<'a> {
 
     /// The font context.
     font_context: ~FontContext,
+
+    /// The URL of the page.
+    url: &'a Url, 
 }
 
 impl<'fc> FlowConstructor<'fc> {
     /// Creates a new flow constructor.
-    pub fn init<'a>(layout_context: &'a mut LayoutContext) -> FlowConstructor<'a> {
+    pub fn init<'a>(layout_context: &'a mut LayoutContext, url: &'a Url) -> FlowConstructor<'a> {
         let font_context = ~FontContext::new(layout_context.font_context_info.clone());
         FlowConstructor {
             layout_context: layout_context,
             next_flow_id: RefCell::new(0),
             font_context: font_context,
+            url: url,
         }
     }
 
@@ -241,14 +250,13 @@ impl<'fc> FlowConstructor<'fc> {
     }
 
     /// Builds the `ImageBoxInfo` for the given image. This is out of line to guide inlining.
-    fn build_box_info_for_image(&mut self, node: ThreadSafeLayoutNode) -> Option<ImageBoxInfo> {
-        // FIXME(pcwalton): Don't copy URLs.
-        match node.image_url() {
-            None => None,
+    fn build_box_info_for_image(&mut self, node: ThreadSafeLayoutNode, url: Option<Url>) -> SpecificBoxInfo {
+        match url {
+            None => GenericBox,
             Some(url) => {
                 // FIXME(pcwalton): The fact that image boxes store the cache within them makes
                 // little sense to me.
-                Some(ImageBoxInfo::new(&node, url, self.layout_context.image_cache.clone()))
+                ImageBox(ImageBoxInfo::new(&node, url, self.layout_context.image_cache.clone()))
             }
         }
     }
@@ -257,13 +265,11 @@ impl<'fc> FlowConstructor<'fc> {
     pub fn build_specific_box_info_for_node(&mut self, node: ThreadSafeLayoutNode)
                                             -> SpecificBoxInfo {
         match node.type_id() {
-            ElementNodeTypeId(HTMLImageElementTypeId) => {
-                match self.build_box_info_for_image(node) {
-                    None => GenericBox,
-                    Some(image_box_info) => ImageBox(image_box_info),
-                }
-            }
+            ElementNodeTypeId(HTMLImageElementTypeId) => self.build_box_info_for_image(node, node.image_url()),
             ElementNodeTypeId(HTMLIframeElementTypeId) => IframeBox(IframeBoxInfo::new(&node)),
+            ElementNodeTypeId(HTMLObjectElementTypeId) => {
+                self.build_box_info_for_image(node, node.get_object_data(self.url))
+            }
             TextNodeTypeId => UnscannedTextBox(UnscannedTextBoxInfo::new(&node)),
             _ => GenericBox,
         }
@@ -709,6 +715,7 @@ impl<'ln> NodeUtils for ThreadSafeLayoutNode<'ln> {
             DocumentFragmentNodeTypeId |
             DocumentNodeTypeId(_) |
             ElementNodeTypeId(HTMLImageElementTypeId) => true,
+            ElementNodeTypeId(HTMLObjectElementTypeId) => self.has_object_data(),
             ElementNodeTypeId(_) => false,
         }
     }
@@ -761,6 +768,39 @@ impl<'ln> NodeUtils for ThreadSafeLayoutNode<'ln> {
     }
 }
 
+/// Methods for interacting with HTMLObjectElement nodes
+trait ObjectElement {
+    /// Returns None if this node is not matching attributes.
+    fn get_type_and_data(self) -> (Option<&'static str>, Option<&'static str>);
+
+    /// Returns true if this node has object data that is correct uri.
+    fn has_object_data(self) -> bool;
+
+    /// Returns the "data" attribute value parsed as a URL    
+    fn get_object_data(self, base_url: &Url) -> Option<Url>;
+}
+
+impl<'ln> ObjectElement for ThreadSafeLayoutNode<'ln> {
+    fn get_type_and_data(self) -> (Option<&'static str>, Option<&'static str>) {
+        (self.with_element(|e| { e.get_attr(&namespace::Null, "type") } ),
+        self.with_element(|e| { e.get_attr(&namespace::Null, "data") } ))
+    }
+
+    fn has_object_data(self) -> bool {
+        match self.get_type_and_data() {
+            (None, Some(uri)) => is_image_data(uri),
+            _ => false
+        }   
+    }
+
+    fn get_object_data(self, base_url: &Url) -> Option<Url> {
+        match self.get_type_and_data() {
+            (None, Some(uri)) if is_image_data(uri) => Some(parse_url(uri, Some(base_url.clone()))),
+            _ => None
+        }
+    }
+}
+
 /// Strips ignorable whitespace from the start of a list of boxes.
 fn strip_ignorable_whitespace_from_start(opt_boxes: &mut Option<~[Box]>) {
     match util::replace(opt_boxes, None) {
diff --git a/src/components/main/layout/layout_task.rs b/src/components/main/layout/layout_task.rs
index 2d79208b6ed..64482cd9803 100644
--- a/src/components/main/layout/layout_task.rs
+++ b/src/components/main/layout/layout_task.rs
@@ -22,6 +22,7 @@ use layout::parallel;
 use layout::util::{LayoutDataAccess, OpaqueNode, LayoutDataWrapper};
 use layout::wrapper::{DomLeafSet, LayoutNode, TLayoutNode, ThreadSafeLayoutNode};
 
+use extra::url::Url;
 use extra::arc::{Arc, MutexArc};
 use geom::rect::Rect;
 use geom::size::Size2D;
@@ -427,9 +428,9 @@ impl LayoutTask {
     /// is intertwined with selector matching, making it difficult to compare directly. It is
     /// marked `#[inline(never)]` to aid benchmarking in sampling profilers.
     #[inline(never)]
-    fn construct_flow_tree(&self, layout_context: &mut LayoutContext, node: LayoutNode) -> ~Flow {
+    fn construct_flow_tree(&self, layout_context: &mut LayoutContext, node: LayoutNode, url: &Url) -> ~Flow {
         let node = ThreadSafeLayoutNode::new(node);
-        node.traverse_postorder_mut(&mut FlowConstructor::init(layout_context));
+        node.traverse_postorder_mut(&mut FlowConstructor::init(layout_context, url));
 
         let mut layout_data_ref = node.mutate_layout_data();
         let result = match *layout_data_ref.get() {
@@ -594,7 +595,7 @@ impl LayoutTask {
             // Construct the flow tree.
             profile(time::LayoutTreeBuilderCategory,
                     self.profiler_chan.clone(),
-                    || self.construct_flow_tree(&mut layout_ctx, *node))
+                    || self.construct_flow_tree(&mut layout_ctx, *node, &data.url))
         });
 
         // Verification of the flow tree, which ensures that all nodes were either marked as leaves
diff --git a/src/components/script/dom/element.rs b/src/components/script/dom/element.rs
index 2eb0553f2f6..12361d7ec85 100644
--- a/src/components/script/dom/element.rs
+++ b/src/components/script/dom/element.rs
@@ -248,6 +248,11 @@ impl Element {
                     iframe.AfterSetAttr(local_name.clone(), value.clone());
                 });
             }
+            ElementNodeTypeId(HTMLObjectElementTypeId) => {
+                abstract_self.with_mut_object_element(|object| {
+                    object.AfterSetAttr(local_name.clone(), value.clone());
+                });
+            }
             _ => ()
         }
 
diff --git a/src/components/script/dom/htmlobjectelement.rs b/src/components/script/dom/htmlobjectelement.rs
index aeb6ad754e9..74f40db40dd 100644
--- a/src/components/script/dom/htmlobjectelement.rs
+++ b/src/components/script/dom/htmlobjectelement.rs
@@ -12,14 +12,21 @@ use dom::validitystate::ValidityState;
 use dom::windowproxy::WindowProxy;
 use servo_util::str::DOMString;
 
+use extra::url::Url;
+use servo_net::image_cache_task;
+use servo_net::image_cache_task::ImageCacheTask;
+use servo_util::url::parse_url;
+use servo_util::namespace::Null;
+use servo_util::url::is_image_data;
+
 pub struct HTMLObjectElement {
-    htmlelement: HTMLElement
+    htmlelement: HTMLElement,
 }
 
 impl HTMLObjectElement {
     pub fn new_inherited(localName: DOMString, document: AbstractDocument) -> HTMLObjectElement {
         HTMLObjectElement {
-            htmlelement: HTMLElement::new_inherited(HTMLObjectElementTypeId, localName, document)
+            htmlelement: HTMLElement::new_inherited(HTMLObjectElementTypeId, localName, document),
         }
     }
 
@@ -30,6 +37,35 @@ impl HTMLObjectElement {
 }
 
 impl HTMLObjectElement {
+
+    // Makes the local `data` member match the status of the `data` attribute and starts
+    /// prefetching the image. This method must be called after `data` is changed.
+    pub fn process_data_url(&mut self, image_cache: ImageCacheTask, url: Option<Url>) {
+        let elem = &mut self.htmlelement.element;
+
+        // TODO: support other values
+        match (elem.get_attribute(Null, "type").map(|x| x.Value()),
+               elem.get_attribute(Null, "data").map(|x| x.Value())) {
+            (None, Some(uri)) => {
+                if is_image_data(uri) {
+                    let data_url = parse_url(uri, url);
+                    // Issue #84
+                    image_cache.send(image_cache_task::Prefetch(data_url));
+                }
+            }
+            _ => { }
+        }
+    }
+
+    pub fn AfterSetAttr(&mut self, name: DOMString, _value: DOMString) {
+        if "data" == name {
+            let document = self.htmlelement.element.node.owner_doc();
+            let window = document.document().window;
+            let url = window.page.url.as_ref().map(|&(ref url, _)| url.clone());
+            self.process_data_url(window.image_cache_task.clone(), url);
+        }
+    }
+
     pub fn Data(&self) -> DOMString {
         ~""
     }
diff --git a/src/components/script/dom/node.rs b/src/components/script/dom/node.rs
index 87e2bddaa37..3f0649fbdac 100644
--- a/src/components/script/dom/node.rs
+++ b/src/components/script/dom/node.rs
@@ -10,11 +10,12 @@ use dom::bindings::utils;
 use dom::characterdata::CharacterData;
 use dom::document::{AbstractDocument, DocumentTypeId};
 use dom::documenttype::DocumentType;
-use dom::element::{Element, ElementTypeId, HTMLImageElementTypeId, HTMLIframeElementTypeId};
+use dom::element::{Element, ElementTypeId, HTMLImageElementTypeId, HTMLIframeElementTypeId, HTMLObjectElementTypeId};
 use dom::element::{HTMLAnchorElementTypeId, HTMLStyleElementTypeId};
 use dom::eventtarget::{AbstractEventTarget, EventTarget, NodeTypeId};
 use dom::htmliframeelement::HTMLIFrameElement;
 use dom::htmlimageelement::HTMLImageElement;
+use dom::htmlobjectelement::HTMLObjectElement;
 use dom::nodelist::{NodeList};
 use dom::text::Text;
 use dom::processinginstruction::ProcessingInstruction;
@@ -488,6 +489,18 @@ impl<'a> AbstractNode {
         self.type_id() == ElementNodeTypeId(HTMLIframeElementTypeId)
     }
 
+    #[inline]
+    pub fn is_object_element(self) -> bool {
+        self.type_id() == ElementNodeTypeId(HTMLObjectElementTypeId)
+    }
+
+    pub fn with_mut_object_element<R>(self, f: |&mut HTMLObjectElement| -> R) -> R {
+        if !self.is_object_element() {
+            fail!(~"node is not an image element");
+        }
+        self.transmute_mut(f)
+    }
+
     pub fn with_mut_iframe_element<R>(self, f: |&mut HTMLIFrameElement| -> R) -> R {
         if !self.is_iframe_element() {
             fail!(~"node is not an iframe element");
diff --git a/src/components/script/html/hubbub_html_parser.rs b/src/components/script/html/hubbub_html_parser.rs
index 9b66e4ecb1a..d388a77b0e3 100644
--- a/src/components/script/html/hubbub_html_parser.rs
+++ b/src/components/script/html/hubbub_html_parser.rs
@@ -392,7 +392,6 @@ pub fn parse_html(cx: *JSContext,
                         image_element.update_image(image_cache_task.clone(), Some(url2.clone()));
                     });
                 }
-
                 _ => {}
             }
 
diff --git a/src/components/util/url.rs b/src/components/util/url.rs
index 6ef650a64cd..004d72e48b8 100644
--- a/src/components/util/url.rs
+++ b/src/components/util/url.rs
@@ -196,3 +196,10 @@ pub fn url_map<T: Clone + 'static>() -> UrlMap<T> {
     HashMap::new()
 }
 
+
+pub fn is_image_data(uri: &str) -> bool {
+    static types: &'static [&'static str] = &[&"data:image/png", &"data:image/gif", &"data:image/jpeg"];
+    types.iter().any(|&type_| uri.starts_with(type_))
+}
+
+
diff --git a/src/test/html/object_element.html b/src/test/html/object_element.html
new file mode 100644
index 00000000000..501e0c049f9
--- /dev/null
+++ b/src/test/html/object_element.html
@@ -0,0 +1,15 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
+<html>
+ <head>
+  <title></title>
+ </head>
+<body>
+<object data="data:application/x-unknown,ERROR">
+  <object data="./nonexistent" type="text/html">
+    <object data="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAGAAAAAYCAYAAAFy7sgCAAAGsUlEQVRo3u2ZbWwcZxHHf3s%2B7LNbO3ZjXBtowprGODRX0qpNQCjmJKuVKhMl1P2AkCwhFOIKkCBSm9IXavGFKAixIAECwkmWo5MrhRI3Ub40IEwQgp6aIDg3Cd6eEqyIHEteah%2B1E69vhw%2BZtTaX8704ZzkKjHS6271nZ56ZZ%2BY%2F%2F%2BdZKF%2FCwYshx3EkkggLsD1v4FQkEZZYLCbAKyG9%2Ba9EIsG6hnUAf8x74K3aUC3j4%2BM54HcsR2oAIomwZOezkv%2FnSHpYNh%2BNCmAE7xv94zvFdd1bHsjMZmQkPSxAJP%2B%2FfuBLwK54PC7JZFKAVJmzXLBt2w%2FMvcDLwIb8QS8CeJ4nkURYIomw7J%2FYJ8BvSiiXptGGxWds2%2Fa9%2Bnaxh%2BYAD%2Bgt04NDgABTpQY2cvvSFLzw86gWeBVwC8SzlOSv2YeBPfmDBoBHgKmR9LBEEmHZfDTqGykqfkUE0nA78BzQGfSgUeP3wNeTXwXg7MwZDhw4UHL6ra2ti79%2FOvljgG8AZ4H64Lhm4MvAocxsRppGG%2FxcXihlwLIs6R%2FfKV2HO%2F26uA94pdDYUKUZUU7W1RQYXA98Gnhaf5%2FXWX0HeAHYoQonqa4sZSOsSWMCWeC9Yko%2BCQwBe4E6oNc0Tc91XTl1%2BaTsn9gnI%2Blhyc5nZWxsrBIkKSbl2tiic3tW53YDEwOKaoFBrcOfqKee53lG9xsPMjV784r%2F4lO%2FpPvyJ9iyZcuvFSaXK5XYeAZ4CDgGvB3MS4B54LQuWYPeuy4iRFsevsXqpuYoqVQKIH2bK1CuDQNo11o4XUzh%2FcDWYIe1LEtyuZx4niee54njOGKapgfsqlL%2Bl2OjEXg8nxrc1dJ0h3hbtL%2BGCtz7KPBF4CuBe9uB15VafE8hr9qylI3HgG8C2%2FK7VyHZoJj7MrBRm30qFotJMpkU27YlHo%2F7Ha5a%2BV%2FKRkSJ4KuKRLVLKapTjB1SzAVIjY2NSXY%2BKyPpYdk%2FsU9OXT4pruv6BdZbBQfKsVGnvWlIe1VB6VQO8JxC1vZYLCbZ%2BaxsPhpdZDyRRFhG0sPiOE6ldKBg2lRg4xF1YCDIIIKN7DGgD3gH%2BBXwejKZfPrs2tPs%2FvPN2bKuYR1nd7xLKBSSJeqoXKnERjPwNWAG%2BLn2rZuM%2B4Tpml6vaWlp4eLcxVusZq5lCgVgOVKJjRqdX86ffL4D5wIoZACnTpw4wRMdT96i%2FImOJxERAs4uVyqxUacF%2FPdiCj%2BjdRBRGFtwXVdG0sPSdbhTmkYbpH98p2RmM2JZlig1vl0GWo4NQ%2Fn%2Bs5pKRXfwjweaxy7TND3HcRZbfC6X8xVPVQlGy7WxVWlO5XRXFXm6EZmrQuSXYyPE3SiVoEhE6Wyr0u2rumO6zv%2B21AFdQAswC1wCMuUCXCmyWQus103Qg8qlDO0lxwOb%2Fl4FiK3AB3VS%2FuKKLtK%2FgbeAnwG%2FvUODuRw%2FFrR0H1UC75fwu8oJ%2FhFsW5VIG%2FBUgEIN6Y65O4AHu4Ap0zQ9y7LEcZyb9lRBUHQcRyzL8unZVBW5bFWAvAp%2BhDQ2g4F47dUYtlU6obXA54DnVdFLekjUGGifh4AFy7LEdV3xj3X9I66m0QZpGm2QrsOd0j%2B%2BU0bSw5KZzYjrun6HWlAd961i4FfCj0aN1Usau%2Bc1lmuXPFwvAEumUut7tQQvAb%2FXb%2FT0bCAej9cODg7yt%2Bm%2F8q2%2F7OUHZ76PnZ1k2p0mJzlykmPancbOTnL0whHs7CQfb%2B5mx2d3sH79%2BtCRI0c6FeaOr9ICrIQfLvA%2B8BGNXxi4R6HrisJVUWrxAVW2oMFf0Aczim8o3kV6enowDIPjF9%2Fk%2BMU3S3rrjzMMg56eHr%2BxP7qKFbASfojG6kpeDGs1tiW53RxwWT%2Bin5q8w4xpQK5evQpAR30H7ZH2khNvj7TTUd8BgD4rqmu1ZKX8qNeY%2BfHz4zlXDgT5E8tpCTUq7XSBC4Euv8227TV9fX1E73%2BYtvo27BmbS9cvFVTY3bSRFza9yOcf6Gfmygy7d%2B%2Fm%2FPnzF4DvrsBLhnJlJfwIKXxv1PheAE4qK6p4H9AGbNKTuhngBPBPXYRe4IemaT5kWZbR19fHNbmGnZ1k4r3U4glDR30Hm5qjbGjsImJEOHbsGHv27JFz5869o0eFq01Jq%2BmHAXwI6FFKagMTgHM7GzFDS%2BoeLSMv7zjzC9x4Y7gxFovVDAwMEI1GaWlpWSzRVCrFwYMH%2FXfxZ4AfAa8B%2F7lDaGg1%2FQgp43lfK0yqtRMuJa3ceKe5DfgYsCYAZ2ngD8CfAkzqTpW7xY%2F%2FSznyX%2FVeUb2kVmX4AAAAAElFTkSuQmCC">
+    ERROR
+    </object>
+  </object>
+</object>
+</body>
+</html>
diff --git a/src/test/ref/basic.list b/src/test/ref/basic.list
index 97e2770f93f..e3e7997a5ae 100644
--- a/src/test/ref/basic.list
+++ b/src/test/ref/basic.list
@@ -33,3 +33,4 @@
 == background_external_stylesheet.html background_ref.html
 == block_image.html 500x300_green.html
 # == simple_iframe.html simple_iframe_ref.html -- disabled due to iframe crashiness
+== object_element_a.html object_element_b.html
diff --git a/src/test/ref/object_element_a.html b/src/test/ref/object_element_a.html
new file mode 100644
index 00000000000..501e0c049f9
--- /dev/null
+++ b/src/test/ref/object_element_a.html
@@ -0,0 +1,15 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
+<html>
+ <head>
+  <title></title>
+ </head>
+<body>
+<object data="data:application/x-unknown,ERROR">
+  <object data="./nonexistent" type="text/html">
+    <object data="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAGAAAAAYCAYAAAFy7sgCAAAGsUlEQVRo3u2ZbWwcZxHHf3s%2B7LNbO3ZjXBtowprGODRX0qpNQCjmJKuVKhMl1P2AkCwhFOIKkCBSm9IXavGFKAixIAECwkmWo5MrhRI3Ub40IEwQgp6aIDg3Cd6eEqyIHEteah%2B1E69vhw%2BZtTaX8704ZzkKjHS6271nZ56ZZ%2BY%2F%2F%2BdZKF%2FCwYshx3EkkggLsD1v4FQkEZZYLCbAKyG9%2Ba9EIsG6hnUAf8x74K3aUC3j4%2BM54HcsR2oAIomwZOezkv%2FnSHpYNh%2BNCmAE7xv94zvFdd1bHsjMZmQkPSxAJP%2B%2FfuBLwK54PC7JZFKAVJmzXLBt2w%2FMvcDLwIb8QS8CeJ4nkURYIomw7J%2FYJ8BvSiiXptGGxWds2%2Fa9%2Bnaxh%2BYAD%2Bgt04NDgABTpQY2cvvSFLzw86gWeBVwC8SzlOSv2YeBPfmDBoBHgKmR9LBEEmHZfDTqGykqfkUE0nA78BzQGfSgUeP3wNeTXwXg7MwZDhw4UHL6ra2ti79%2FOvljgG8AZ4H64Lhm4MvAocxsRppGG%2FxcXihlwLIs6R%2FfKV2HO%2F26uA94pdDYUKUZUU7W1RQYXA98Gnhaf5%2FXWX0HeAHYoQonqa4sZSOsSWMCWeC9Yko%2BCQwBe4E6oNc0Tc91XTl1%2BaTsn9gnI%2Blhyc5nZWxsrBIkKSbl2tiic3tW53YDEwOKaoFBrcOfqKee53lG9xsPMjV784r%2F4lO%2FpPvyJ9iyZcuvFSaXK5XYeAZ4CDgGvB3MS4B54LQuWYPeuy4iRFsevsXqpuYoqVQKIH2bK1CuDQNo11o4XUzh%2FcDWYIe1LEtyuZx4niee54njOGKapgfsqlL%2Bl2OjEXg8nxrc1dJ0h3hbtL%2BGCtz7KPBF4CuBe9uB15VafE8hr9qylI3HgG8C2%2FK7VyHZoJj7MrBRm30qFotJMpkU27YlHo%2F7Ha5a%2BV%2FKRkSJ4KuKRLVLKapTjB1SzAVIjY2NSXY%2BKyPpYdk%2FsU9OXT4pruv6BdZbBQfKsVGnvWlIe1VB6VQO8JxC1vZYLCbZ%2BaxsPhpdZDyRRFhG0sPiOE6ldKBg2lRg4xF1YCDIIIKN7DGgD3gH%2BBXwejKZfPrs2tPs%2FvPN2bKuYR1nd7xLKBSSJeqoXKnERjPwNWAG%2BLn2rZuM%2B4Tpml6vaWlp4eLcxVusZq5lCgVgOVKJjRqdX86ffL4D5wIoZACnTpw4wRMdT96i%2FImOJxERAs4uVyqxUacF%2FPdiCj%2BjdRBRGFtwXVdG0sPSdbhTmkYbpH98p2RmM2JZlig1vl0GWo4NQ%2Fn%2Bs5pKRXfwjweaxy7TND3HcRZbfC6X8xVPVQlGy7WxVWlO5XRXFXm6EZmrQuSXYyPE3SiVoEhE6Wyr0u2rumO6zv%2B21AFdQAswC1wCMuUCXCmyWQus103Qg8qlDO0lxwOb%2Fl4FiK3AB3VS%2FuKKLtK%2FgbeAnwG%2FvUODuRw%2FFrR0H1UC75fwu8oJ%2FhFsW5VIG%2FBUgEIN6Y65O4AHu4Ap0zQ9y7LEcZyb9lRBUHQcRyzL8unZVBW5bFWAvAp%2BhDQ2g4F47dUYtlU6obXA54DnVdFLekjUGGifh4AFy7LEdV3xj3X9I66m0QZpGm2QrsOd0j%2B%2BU0bSw5KZzYjrun6HWlAd961i4FfCj0aN1Usau%2Bc1lmuXPFwvAEumUut7tQQvAb%2FXb%2FT0bCAej9cODg7yt%2Bm%2F8q2%2F7OUHZ76PnZ1k2p0mJzlykmPancbOTnL0whHs7CQfb%2B5mx2d3sH79%2BtCRI0c6FeaOr9ICrIQfLvA%2B8BGNXxi4R6HrisJVUWrxAVW2oMFf0Aczim8o3kV6enowDIPjF9%2Fk%2BMU3S3rrjzMMg56eHr%2BxP7qKFbASfojG6kpeDGs1tiW53RxwWT%2Bin5q8w4xpQK5evQpAR30H7ZH2khNvj7TTUd8BgD4rqmu1ZKX8qNeY%2BfHz4zlXDgT5E8tpCTUq7XSBC4Euv8227TV9fX1E73%2BYtvo27BmbS9cvFVTY3bSRFza9yOcf6Gfmygy7d%2B%2Fm%2FPnzF4DvrsBLhnJlJfwIKXxv1PheAE4qK6p4H9AGbNKTuhngBPBPXYRe4IemaT5kWZbR19fHNbmGnZ1k4r3U4glDR30Hm5qjbGjsImJEOHbsGHv27JFz5869o0eFq01Jq%2BmHAXwI6FFKagMTgHM7GzFDS%2BoeLSMv7zjzC9x4Y7gxFovVDAwMEI1GaWlpWSzRVCrFwYMH%2FXfxZ4AfAa8B%2F7lDaGg1%2FQgp43lfK0yqtRMuJa3ceKe5DfgYsCYAZ2ngD8CfAkzqTpW7xY%2F%2FSznyX%2FVeUb2kVmX4AAAAAElFTkSuQmCC">
+    ERROR
+    </object>
+  </object>
+</object>
+</body>
+</html>
diff --git a/src/test/ref/object_element_b.html b/src/test/ref/object_element_b.html
new file mode 100644
index 00000000000..ae6d8ab3648
--- /dev/null
+++ b/src/test/ref/object_element_b.html
@@ -0,0 +1,9 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
+<html>
+ <head>
+  <title></title>
+ </head>
+<body>
+<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAGAAAAAYCAYAAAFy7sgCAAAGsUlEQVRo3u2ZbWwcZxHHf3s%2B7LNbO3ZjXBtowprGODRX0qpNQCjmJKuVKhMl1P2AkCwhFOIKkCBSm9IXavGFKAixIAECwkmWo5MrhRI3Ub40IEwQgp6aIDg3Cd6eEqyIHEteah%2B1E69vhw%2BZtTaX8704ZzkKjHS6271nZ56ZZ%2BY%2F%2F%2BdZKF%2FCwYshx3EkkggLsD1v4FQkEZZYLCbAKyG9%2Ba9EIsG6hnUAf8x74K3aUC3j4%2BM54HcsR2oAIomwZOezkv%2FnSHpYNh%2BNCmAE7xv94zvFdd1bHsjMZmQkPSxAJP%2B%2FfuBLwK54PC7JZFKAVJmzXLBt2w%2FMvcDLwIb8QS8CeJ4nkURYIomw7J%2FYJ8BvSiiXptGGxWds2%2Fa9%2Bnaxh%2BYAD%2Bgt04NDgABTpQY2cvvSFLzw86gWeBVwC8SzlOSv2YeBPfmDBoBHgKmR9LBEEmHZfDTqGykqfkUE0nA78BzQGfSgUeP3wNeTXwXg7MwZDhw4UHL6ra2ti79%2FOvljgG8AZ4H64Lhm4MvAocxsRppGG%2FxcXihlwLIs6R%2FfKV2HO%2F26uA94pdDYUKUZUU7W1RQYXA98Gnhaf5%2FXWX0HeAHYoQonqa4sZSOsSWMCWeC9Yko%2BCQwBe4E6oNc0Tc91XTl1%2BaTsn9gnI%2Blhyc5nZWxsrBIkKSbl2tiic3tW53YDEwOKaoFBrcOfqKee53lG9xsPMjV784r%2F4lO%2FpPvyJ9iyZcuvFSaXK5XYeAZ4CDgGvB3MS4B54LQuWYPeuy4iRFsevsXqpuYoqVQKIH2bK1CuDQNo11o4XUzh%2FcDWYIe1LEtyuZx4niee54njOGKapgfsqlL%2Bl2OjEXg8nxrc1dJ0h3hbtL%2BGCtz7KPBF4CuBe9uB15VafE8hr9qylI3HgG8C2%2FK7VyHZoJj7MrBRm30qFotJMpkU27YlHo%2F7Ha5a%2BV%2FKRkSJ4KuKRLVLKapTjB1SzAVIjY2NSXY%2BKyPpYdk%2FsU9OXT4pruv6BdZbBQfKsVGnvWlIe1VB6VQO8JxC1vZYLCbZ%2BaxsPhpdZDyRRFhG0sPiOE6ldKBg2lRg4xF1YCDIIIKN7DGgD3gH%2BBXwejKZfPrs2tPs%2FvPN2bKuYR1nd7xLKBSSJeqoXKnERjPwNWAG%2BLn2rZuM%2B4Tpml6vaWlp4eLcxVusZq5lCgVgOVKJjRqdX86ffL4D5wIoZACnTpw4wRMdT96i%2FImOJxERAs4uVyqxUacF%2FPdiCj%2BjdRBRGFtwXVdG0sPSdbhTmkYbpH98p2RmM2JZlig1vl0GWo4NQ%2Fn%2Bs5pKRXfwjweaxy7TND3HcRZbfC6X8xVPVQlGy7WxVWlO5XRXFXm6EZmrQuSXYyPE3SiVoEhE6Wyr0u2rumO6zv%2B21AFdQAswC1wCMuUCXCmyWQus103Qg8qlDO0lxwOb%2Fl4FiK3AB3VS%2FuKKLtK%2FgbeAnwG%2FvUODuRw%2FFrR0H1UC75fwu8oJ%2FhFsW5VIG%2FBUgEIN6Y65O4AHu4Ap0zQ9y7LEcZyb9lRBUHQcRyzL8unZVBW5bFWAvAp%2BhDQ2g4F47dUYtlU6obXA54DnVdFLekjUGGifh4AFy7LEdV3xj3X9I66m0QZpGm2QrsOd0j%2B%2BU0bSw5KZzYjrun6HWlAd961i4FfCj0aN1Usau%2Bc1lmuXPFwvAEumUut7tQQvAb%2FXb%2FT0bCAej9cODg7yt%2Bm%2F8q2%2F7OUHZ76PnZ1k2p0mJzlykmPancbOTnL0whHs7CQfb%2B5mx2d3sH79%2BtCRI0c6FeaOr9ICrIQfLvA%2B8BGNXxi4R6HrisJVUWrxAVW2oMFf0Aczim8o3kV6enowDIPjF9%2Fk%2BMU3S3rrjzMMg56eHr%2BxP7qKFbASfojG6kpeDGs1tiW53RxwWT%2Bin5q8w4xpQK5evQpAR30H7ZH2khNvj7TTUd8BgD4rqmu1ZKX8qNeY%2BfHz4zlXDgT5E8tpCTUq7XSBC4Euv8227TV9fX1E73%2BYtvo27BmbS9cvFVTY3bSRFza9yOcf6Gfmygy7d%2B%2Fm%2FPnzF4DvrsBLhnJlJfwIKXxv1PheAE4qK6p4H9AGbNKTuhngBPBPXYRe4IemaT5kWZbR19fHNbmGnZ1k4r3U4glDR30Hm5qjbGjsImJEOHbsGHv27JFz5869o0eFq01Jq%2BmHAXwI6FFKagMTgHM7GzFDS%2BoeLSMv7zjzC9x4Y7gxFovVDAwMEI1GaWlpWSzRVCrFwYMH%2FXfxZ4AfAa8B%2F7lDaGg1%2FQgp43lfK0yqtRMuJa3ceKe5DfgYsCYAZ2ngD8CfAkzqTpW7xY%2F%2FSznyX%2FVeUb2kVmX4AAAAAElFTkSuQmCC"/>
+</body>
+</html>
\ No newline at end of file