Made Isolate a mandatory parameter for everything Handle-related.

src/messages.h

Index: src/messages.h
diff --git a/src/messages.h b/src/messages.h
index 52dc4fe87db6f167c2dfd5d7470961b7a8f2c626..3361abe2314448006b16d902c7f96e006b094084 100644
--- a/src/messages.h
+++ b/src/messages.h
@@ -105,7 +105,7 @@ class MessageHandler {
   static void DefaultMessageReport(Isolate* isolate,
                                    const MessageLocation* loc,
                                    Handle<Object> message_obj);
-  static Handle<String> GetMessage(Handle<Object> data);
+  static Handle<String> GetMessage(Isolate* isolate, Handle<Object> data);
   static SmartArrayPointer<char> GetLocalizedMessage(Isolate* isolate,
                                                      Handle<Object> data);
 };