6 files changed, 20 insertions, 14 deletions
diff --git a/components/script/dom/activation.rs b/components/script/dom/activation.rs
index e4a54112e58..97bc66f5362 100644
--- a/components/script/dom/activation.rs
+++ b/components/script/dom/activation.rs
@@ -49,7 +49,7 @@ pub trait Activatable : Copy {
                                     0, None).root();
         let event: JSRef<Event> = EventCast::from_ref(*mouse);
         event.set_trusted(true);
-        target.dispatch_event_with_target(None, event).ok();
+        target.dispatch_event(event);
 
         // Step 5
         if event.DefaultPrevented() {
diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index e24407d7957..1dc277e0fc1 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -1262,7 +1262,7 @@ impl<'a> ActivationElementHelpers<'a> for JSRef<'a, Element> {
                 Some(elem) => {
                     // Step 5-6
                     elem.pre_click_activation();
-                    target.dispatch_event_with_target(None, event).ok();
+                    target.dispatch_event(event);
                     if !event.DefaultPrevented() {
                         // post click activation
                         elem.activation_behavior();
@@ -1271,10 +1271,10 @@ impl<'a> ActivationElementHelpers<'a> for JSRef<'a, Element> {
                     }
                 }
                 // Step 6
-                None => {target.dispatch_event_with_target(None, event).ok();}
+                None => {target.dispatch_event(event);}
             },
             // Step 6
-            None => {target.dispatch_event_with_target(None, event).ok();}
+            None => {target.dispatch_event(event);}
         }
         // Step 7
         self.set_click_in_progress(false);
diff --git a/components/script/dom/eventdispatcher.rs b/components/script/dom/eventdispatcher.rs
index bdfb98c7bae..74ffc1f5136 100644
--- a/components/script/dom/eventdispatcher.rs
+++ b/components/script/dom/eventdispatcher.rs
@@ -16,6 +16,7 @@ pub fn dispatch_event<'a, 'b>(target: JSRef<'a, EventTarget>,
                               pseudo_target: Option<JSRef<'b, EventTarget>>,
                               event: JSRef<Event>) -> bool {
     assert!(!event.dispatching());
+    assert!(event.initialized());
 
     event.set_target(match pseudo_target {
         Some(pseudo_target) => pseudo_target,
diff --git a/components/script/dom/eventtarget.rs b/components/script/dom/eventtarget.rs
index 151a1ac939a..394b66e6acc 100644
--- a/components/script/dom/eventtarget.rs
+++ b/components/script/dom/eventtarget.rs
@@ -107,7 +107,8 @@ impl EventTarget {
 pub trait EventTargetHelpers {
     fn dispatch_event_with_target(self,
                                   target: Option<JSRef<EventTarget>>,
-                                  event: JSRef<Event>) -> Fallible<bool>;
+                                  event: JSRef<Event>) -> bool;
+    fn dispatch_event(self, event: JSRef<Event>) -> bool;
     fn set_inline_event_listener(self,
                                  ty: DOMString,
                                  listener: Option<EventListener>);
@@ -128,11 +129,12 @@ pub trait EventTargetHelpers {
 impl<'a> EventTargetHelpers for JSRef<'a, EventTarget> {
     fn dispatch_event_with_target(self,
                                   target: Option<JSRef<EventTarget>>,
-                                  event: JSRef<Event>) -> Fallible<bool> {
-        if event.dispatching() || !event.initialized() {
-            return Err(InvalidState);
-        }
-        Ok(dispatch_event(self, target, event))
+                                  event: JSRef<Event>) -> bool {
+        dispatch_event(self, target, event)
+    }
+
+    fn dispatch_event(self, event: JSRef<Event>) -> bool {
+        self.dispatch_event_with_target(None, event)
     }
 
     fn set_inline_event_listener(self,
@@ -290,7 +292,10 @@ impl<'a> EventTargetMethods for JSRef<'a, EventTarget> {
     }
 
     fn DispatchEvent(self, event: JSRef<Event>) -> Fallible<bool> {
-        self.dispatch_event_with_target(None, event)
+        if event.dispatching() || !event.initialized() {
+            return Err(InvalidState);
+        }
+        Ok(self.dispatch_event(event))
     }
 }
 
diff --git a/components/script/dom/messageevent.rs b/components/script/dom/messageevent.rs
index 32842fd2897..9dda3ccc8cc 100644
--- a/components/script/dom/messageevent.rs
+++ b/components/script/dom/messageevent.rs
@@ -81,7 +81,7 @@ impl MessageEvent {
             scope, "message".to_string(), false, false, message,
             "".to_string(), "".to_string()).root();
         let event: JSRef<Event> = EventCast::from_ref(*messageevent);
-        target.dispatch_event_with_target(None, event).unwrap();
+        target.dispatch_event(event);
     }
 }
 
diff --git a/components/script/dom/xmlhttprequest.rs b/components/script/dom/xmlhttprequest.rs
index 0f8e770d8d5..b5f580fc6a5 100644
--- a/components/script/dom/xmlhttprequest.rs
+++ b/components/script/dom/xmlhttprequest.rs
@@ -817,7 +817,7 @@ impl<'a> PrivateXMLHttpRequestHelpers for JSRef<'a, XMLHttpRequest> {
                                "readystatechange".to_string(),
                                DoesNotBubble, Cancelable).root();
         let target: JSRef<EventTarget> = EventTargetCast::from_ref(self);
-        target.dispatch_event_with_target(None, *event).ok();
+        target.dispatch_event(*event);
     }
 
     fn process_partial_response(self, progress: XHRProgress) {
@@ -957,7 +957,7 @@ impl<'a> PrivateXMLHttpRequestHelpers for JSRef<'a, XMLHttpRequest> {
             EventTargetCast::from_ref(self)
         };
         let event: JSRef<Event> = EventCast::from_ref(*progressevent);
-        target.dispatch_event_with_target(None, event).ok();
+        target.dispatch_event(event);
     }
 
     fn dispatch_upload_progress_event(self, type_: DOMString, partial_load: Option<u64>) {