Auto merge of #8558 - jdm:crossoriginiframeload, r=glennw

Dispatch load events for cross origin iframes. Resolves #6672.

Splitting it out from #6677.

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2 files changed, 34 insertions, 15 deletions

diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 31f67f33801..92942012def 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -58,7 +58,7 @@ use dom::keyboardevent::KeyboardEvent;
 use dom::location::Location;
 use dom::messageevent::MessageEvent;
 use dom::mouseevent::MouseEvent;
-use dom::node::{self, CloneChildrenFlag, Node, NodeDamage, window_from_node};
+use dom::node::{self, CloneChildrenFlag, Node, NodeDamage};
 use dom::nodeiterator::NodeIterator;
 use dom::nodelist::NodeList;
 use dom::processinginstruction::ProcessingInstruction;
@@ -79,9 +79,9 @@ use layout_interface::{HitTestResponse, MouseOverResponse};
 use layout_interface::{LayoutChan, Msg};
 use layout_interface::{ReflowGoal, ReflowQueryType};
 use msg::compositor_msg::ScriptToCompositorMsg;
-use msg::constellation_msg::AnimationState;
 use msg::constellation_msg::ScriptMsg as ConstellationMsg;
 use msg::constellation_msg::{ALT, CONTROL, SHIFT, SUPER};
+use msg::constellation_msg::{AnimationState, PipelineId};
 use msg::constellation_msg::{ConstellationChan, FocusType, Key, KeyModifiers, KeyState, MozBrowserEvent, SubpageId};
 use net_traits::ControlMsg::{GetCookiesForUrl, SetCookiesForUrl};
 use net_traits::CookieSource::NonHTTP;
@@ -1333,6 +1333,14 @@ impl Document {
             .find(|node| node.subpage_id() == Some(subpage_id))
     }
 
+    /// Find an iframe element in the document.
+    pub fn find_iframe_by_pipeline(&self, pipeline: PipelineId) -> Option<Root<HTMLIFrameElement>> {
+        self.upcast::<Node>()
+            .traverse_preorder()
+            .filter_map(Root::downcast::<HTMLIFrameElement>)
+            .find(|node| node.pipeline() == Some(pipeline))
+    }
+
     pub fn get_dom_loading(&self) -> u64 {
         self.dom_loading.get()
     }
@@ -2433,18 +2441,6 @@ impl DocumentProgressHandler {
         event.set_trusted(true);
         let _ = wintarget.dispatch_event_with_target(document.upcast(), &event);
 
-        let browsing_context = window.browsing_context();
-        let browsing_context = browsing_context.as_ref().unwrap();
-
-        if let Some(frame_element) = browsing_context.frame_element() {
-            let frame_window = window_from_node(frame_element);
-            let event = Event::new(GlobalRef::Window(frame_window.r()),
-                                   DOMString::from("load"),
-                                   EventBubbles::DoesNotBubble,
-                                   EventCancelable::NotCancelable);
-            event.fire(frame_element.upcast());
-        };
-
         document.notify_constellation_load();
 
         // https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowserloadend
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 66bade67a7d..78400b6d49a 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -16,7 +16,7 @@ use dom::bindings::reflector::Reflectable;
 use dom::customevent::CustomEvent;
 use dom::document::Document;
 use dom::element::{AttributeMutation, Element, RawLayoutElementHelpers};
-use dom::event::Event;
+use dom::event::{Event, EventBubbles, EventCancelable};
 use dom::htmlelement::HTMLElement;
 use dom::node::{Node, window_from_node};
 use dom::urlhelper::UrlHelper;
@@ -189,6 +189,29 @@ impl HTMLIFrameElement {
     pub fn subpage_id(&self) -> Option<SubpageId> {
         self.subpage_id.get()
     }
+
+    pub fn pipeline(&self) -> Option<PipelineId> {
+        self.pipeline_id.get()
+    }
+
+    /// https://html.spec.whatwg.org/multipage/#iframe-load-event-steps steps 1-4
+    pub fn iframe_load_event_steps(&self) {
+        // TODO A cross-origin child document would not be easily accessible
+        //      from this script thread. It's unclear how to implement
+        //      steps 2, 3, and 5 efficiently in this case.
+        // TODO Step 2 - check child document `mute iframe load` flag
+        // TODO Step 3 - set child document  `mut iframe load` flag
+
+        // Step 4
+        let window = window_from_node(self);
+        let event = Event::new(GlobalRef::Window(window.r()),
+                               DOMString::from("load".to_owned()),
+                               EventBubbles::DoesNotBubble,
+                               EventCancelable::NotCancelable);
+        event.fire(self.upcast());
+
+        // TODO Step 5 - unset child document `mut iframe load` flag
+    }
 }
 
 pub trait HTMLIFrameElementLayoutMethods {