Auto merge of #9734 - nox:finish-event-dispatch, r=Ms2ger

Fix the "get the parent" loop when dispatching event (fixes #6733)

The DOM specification says:

> A document's get the parent algorithm, given an event, returns null
> if event's type attribute value is "load" or document does not have
> a browsing context, and the document's associated Window object
> otherwise.

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1 files changed, 8 insertions, 0 deletions

diff --git a/components/script/dom/eventdispatcher.rs b/components/script/dom/eventdispatcher.rs
index 28a269b7429..f80a217658b 100644
--- a/components/script/dom/eventdispatcher.rs
+++ b/components/script/dom/eventdispatcher.rs
@@ -10,6 +10,7 @@ use dom::bindings::inheritance::Castable;
 use dom::bindings::js::{JS, Root, RootedReference};
 use dom::bindings::reflector::Reflectable;
 use dom::bindings::trace::RootedVec;
+use dom::document::Document;
 use dom::event::{Event, EventPhase};
 use dom::eventtarget::{CompiledEventListener, EventTarget, ListenerPhase};
 use dom::node::Node;
@@ -153,6 +154,13 @@ pub fn dispatch_event(target: &EventTarget, pseudo_target: Option<&EventTarget>,
         for ancestor in target_node.ancestors() {
             chain.push(JS::from_ref(ancestor.upcast()));
         }
+        let top_most_ancestor_or_target =
+            Root::from_ref(chain.r().last().cloned().unwrap_or(target));
+        if let Some(document) = Root::downcast::<Document>(top_most_ancestor_or_target) {
+            if event.type_() != atom!("load") && document.browsing_context().is_some() {
+                chain.push(JS::from_ref(document.window().upcast()));
+            }
+        }
     }
 
     dispatch_to_listeners(event, target, chain.r());