begin messageport, transferable objects, impl

Accept transfer argument for StructuredCloneData::write

Allow structured clone reads to return a boolean

Add Transferable trait

Add basic skeletons to MessagePort

Implement transfer and transfer-receiving steps on MessagePort

Use transfer and transfer_receive in StructuredClone callbacks

Implement MessageChannel

Freeze the array object for the MessageEvent ports attribute

Implement transfer argument on window.postMessage

Use ReentrantMutex instead for MessagePortInternal

Accept origin as a parameter in dispatch_jsval

Fix BorrowMut crash with pending_port_message

Detach port on closure and check for detached during transfer

Enable webmessaging tests

fix webidl

fix

components/profile/time.rs

@@ -136,6 +136,7 @@ impl Formattable for ProfilerCategory {
             ProfilerCategory::ScriptParseHTML => "Script Parse HTML",
             ProfilerCategory::ScriptParseXML => "Script Parse XML",
             ProfilerCategory::ScriptPlannedNavigation => "Script Planned Navigation",
+            ProfilerCategory::ScriptPortMessage => "Script Port Message",
             ProfilerCategory::ScriptResize => "Script Resize",
             ProfilerCategory::ScriptEvent => "Script Event",
             ProfilerCategory::ScriptUpdateReplacedElement => "Script Update Replaced Element",