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