Pass isolate to ScriptPromise and ScriptString constructors

Source/bindings/v8/ScriptString.h

Index: Source/bindings/v8/ScriptString.h
diff --git a/Source/bindings/v8/ScriptString.h b/Source/bindings/v8/ScriptString.h
index f3a713404275151af3e921e7f562769278d084ad..ed493f8bf4866b4fa7c815a4df81a456703301f0 100644
--- a/Source/bindings/v8/ScriptString.h
+++ b/Source/bindings/v8/ScriptString.h
@@ -40,8 +40,7 @@ namespace WebCore {
 class ScriptString : public ScriptValue {
 public:
     ScriptString() { }
-    // FIXME: This constructor should take an isolate.
-    explicit ScriptString(v8::Handle<v8::String> value) : ScriptValue(value, v8::Isolate::GetCurrent()) { }
+    ScriptString(v8::Handle<v8::String> value, v8::Isolate* isolate) : ScriptValue(value, isolate) { }
 
     ScriptString concatenateWith(const String&);
     String flattenToString() const;