[webcrypto] Add parameter parsing for AES-GCM.

Source/bindings/v8/Dictionary.cpp

Index: Source/bindings/v8/Dictionary.cpp
diff --git a/Source/bindings/v8/Dictionary.cpp b/Source/bindings/v8/Dictionary.cpp
index fe255329c6267c2082bb7c9d0508402a75e817d9..a834e46ba6a523ce348d1d21b71b0b0287917f54 100644
--- a/Source/bindings/v8/Dictionary.cpp
+++ b/Source/bindings/v8/Dictionary.cpp
@@ -431,10 +431,19 @@ bool Dictionary::get(const String& key, RefPtr<Uint8Array>& value) const
 
 bool Dictionary::get(const String& key, RefPtr<ArrayBufferView>& value) const
 {
+    bool unused;
+    return get(key, value, unused);
+}
+
+bool Dictionary::get(const String& key, RefPtr<ArrayBufferView>& value, bool& hasValue) const
+{
     v8::Local<v8::Value> v8Value;
-    if (!getKey(key, v8Value))
+    if (!getKey(key, v8Value)) {
+        hasValue = false;

[sof, 2014/02/25 22:01:45]

Hmm, this extra reference argument seems to end up with the same value as the
return value. Why do you need it?

[eroman, 2014/02/25 22:23:29]

You are right, my mistake.
Will remove

[eroman, 2014/02/25 22:31:00]

Thanks sof! updated.

         return false;
+    }
 
+    hasValue = true;
     value = V8ArrayBufferView::toNativeWithTypeCheck(m_isolate, v8Value);
     return true;
 }