Use ExceptionState to throw exceptions when converting arrays

Source/bindings/core/v8/DictionaryHelperForCore.cpp

Index: Source/bindings/core/v8/DictionaryHelperForCore.cpp
diff --git a/Source/bindings/core/v8/DictionaryHelperForCore.cpp b/Source/bindings/core/v8/DictionaryHelperForCore.cpp
index e6dbd86e38d776781f02fdd463bd9250c0fbe212..16f64a943b891c60d13d55a9e3007ff67839e8ae 100644
--- a/Source/bindings/core/v8/DictionaryHelperForCore.cpp
+++ b/Source/bindings/core/v8/DictionaryHelperForCore.cpp
@@ -275,9 +275,10 @@ bool DictionaryHelper::get(const Dictionary& dictionary, const String& key, Mess
     ASSERT(dictionary.isolate() == v8::Isolate::GetCurrent());
     if (blink::isUndefinedOrNull(v8Value))
         return true;
-    bool success = false;
-    value = toRefPtrWillBeMemberNativeArray<MessagePort, V8MessagePort>(v8Value, key, dictionary.isolate(), &success);
-    return success;
+    // FIXME (before landing): We can't use a NonThrowableExceptionState here; figure out what to do instead.

[Jens Widell, 2014/09/11 13:22:31]

Need to resolve this. I thought I couldn't create a full ExceptionState here,
but maybe I can, using dictionary.v8value() for the |creationContext| argument?

Otherwise passing in an ExceptionState& to this method would be the natural
approach, I guess, but that will expand the patch even more, and I wasn't sure
if we really wanted to spend too much effort on Dictionary/DictionaryHelper at
this point.

+    NonThrowableExceptionState exceptionState;
+    value = toRefPtrWillBeMemberNativeArray<MessagePort, V8MessagePort>(v8Value, key, dictionary.isolate(), exceptionState);
+    return !exceptionState.throwIfNeeded();
 }
 
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