[dartium] Dart half of ScriptValue refactoring.

Source/bindings/dart/DartUtilities.cpp

Index: Source/bindings/dart/DartUtilities.cpp
diff --git a/Source/bindings/dart/DartUtilities.cpp b/Source/bindings/dart/DartUtilities.cpp
index c82c8e0192649c86b173ce2d5126c373607bdcb8..02681c2fc32b4f1c6e4d9fbef06d3f9a813c6470 100644
--- a/Source/bindings/dart/DartUtilities.cpp
+++ b/Source/bindings/dart/DartUtilities.cpp
@@ -374,7 +374,7 @@ Dart_Handle DartUtilities::numberToDart(double value)
 
 ScriptValue DartUtilities::dartToScriptValue(Dart_Handle object, Dart_Handle& exception)
 {
-    return ScriptValue(V8Converter::toV8(object, exception), v8::Isolate::GetCurrent());
+    return ScriptValue(DartScriptValue::create(object));
 }
 
 Dart_Handle DartUtilities::scriptValueToDart(const ScriptValue& value)
@@ -382,6 +382,12 @@ Dart_Handle DartUtilities::scriptValueToDart(const ScriptValue& value)
     if (value.hasNoValue()) {
         return Dart_Null();
     }
+    AbstractScriptValue* scriptValue = value.scriptValue();
+    if (scriptValue->isDart()) {
+        DartScriptValue* dartScriptValue = static_cast<DartScriptValue*>(scriptValue);
+        return dartScriptValue->dartValue();
+    }
+    // FIXMEMULTIVM: Should not be converting from V8 values. Major culprit is IDB.
     // FIXME: better error handling.
     Dart_Handle exception = 0;
     return V8Converter::toDart(value.v8Value(), exception);