Trigger `window.onerror` only for exceptions thrown in the same world.

Source/core/dom/ErrorEvent.cpp

Index: Source/core/dom/ErrorEvent.cpp
diff --git a/Source/core/dom/ErrorEvent.cpp b/Source/core/dom/ErrorEvent.cpp
index ecb3d4b842da6957d0d6b775c7eb058957df44ab..63d72caf4277b1198e98f6c135e8491b7d1ab8ed 100644
--- a/Source/core/dom/ErrorEvent.cpp
+++ b/Source/core/dom/ErrorEvent.cpp
@@ -54,16 +54,18 @@ ErrorEvent::ErrorEvent(const AtomicString& type, const ErrorEventInit& initializ
     , m_fileName(initializer.filename)
     , m_lineNumber(initializer.lineno)
     , m_columnNumber(initializer.colno)
+    , m_world(0)

[adamk, 2013/09/05 19:24:20]

Why 0?

[Mike West, 2013/09/06 11:57:03]

Laziness. I've changed this to pull in the current DOMWrapperWorld. I'd prefer
for that to be done in the generated bindings code, but I don't think it's worth
adding a custom constructor to V8ErrorEvent to make that happen. Pulling
'DOMWrapperWorld::current()' here is the lesser of those two evils.

 {
     ScriptWrappable::init(this);
 }
 
-ErrorEvent::ErrorEvent(const String& message, const String& fileName, unsigned lineNumber, unsigned columnNumber)
+ErrorEvent::ErrorEvent(const String& message, const String& fileName, unsigned lineNumber, unsigned columnNumber, DOMWrapperWorld* world)
     : Event(eventNames().errorEvent, false, true)
     , m_sanitizedMessage(message)
     , m_fileName(fileName)
     , m_lineNumber(lineNumber)
     , m_columnNumber(columnNumber)
+    , m_world(world)
 {
     ScriptWrappable::init(this);
 }