Implement issue 549 Make V8 call DebugMessageDispatchHandler with Locker locked

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 25461019724892791a79ff493107e6c892306e7b..322c90fc5aca08f71487a68c9d2349c6a307b8d8 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -3669,7 +3669,6 @@ void Debug::SetMessageHandler(v8::Debug::MessageHandler handler,
 void Debug::SetMessageHandler2(v8::Debug::MessageHandler2 handler) {
   EnsureInitialized("v8::Debug::SetMessageHandler");
   ENTER_V8;
-  HandleScope scope;
   i::Debugger::SetMessageHandler(handler);
 }
 
@@ -3691,10 +3690,10 @@ void Debug::SetHostDispatchHandler(HostDispatchHandler handler,
 
 
 void Debug::SetDebugMessageDispatchHandler(
-    DebugMessageDispatchHandler handler) {
+    DebugMessageDispatchHandler handler, bool provide_locker) {
   EnsureInitialized("v8::Debug::SetDebugMessageDispatchHandler");
   ENTER_V8;
-  i::Debugger::SetDebugMessageDispatchHandler(handler);
+  i::Debugger::SetDebugMessageDispatchHandler(handler, provide_locker);
 }