Oilpan: move MessagePortArray to the heap.

Source/bindings/v8/SerializedScriptValue.cpp

Index: Source/bindings/v8/SerializedScriptValue.cpp
diff --git a/Source/bindings/v8/SerializedScriptValue.cpp b/Source/bindings/v8/SerializedScriptValue.cpp
index e11af11b6515e6b3ab29b28eba5bbed8754fd690..f3047005e83e8133e3e4346540404d5cb7f7f6d3 100644
--- a/Source/bindings/v8/SerializedScriptValue.cpp
+++ b/Source/bindings/v8/SerializedScriptValue.cpp
@@ -3018,7 +3018,7 @@ bool SerializedScriptValue::extractTransferables(v8::Local<v8::Value> value, int
         }
         // Validation of Objects implementing an interface, per WebIDL spec 4.1.15.
         if (V8MessagePort::hasInstance(transferrable, isolate)) {
-            RefPtr<MessagePort> port = V8MessagePort::toNative(v8::Handle<v8::Object>::Cast(transferrable));
+            RefPtrWillBeRawPtr<MessagePort> port = V8MessagePort::toNative(v8::Handle<v8::Object>::Cast(transferrable));
             // Check for duplicate MessagePorts.
             if (ports.contains(port)) {
                 exceptionState.throwDOMException(DataCloneError, "Message port at index " + String::number(i) + " is a duplicate of an earlier port.");