binidngs: Make callInternalFunction return MaybeLocal

Source/bindings/core/v8/V8PerIsolateData.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 224 matching lines @@
     // changes to the Function prototype chain or toString function are
     // reflected when printing DOM constructors. The only wart is that
     // changes to a DOM constructor's toString's toString will cause the
     // toString of the DOM constructor itself to change. This is extremely
     // obscure and unlikely to be a problem.
     v8::Handle<v8::Value> value = info.Callee()->Get(v8AtomicString(info.GetIsolate(), "toString"));
     if (!value->IsFunction()) {
         v8SetReturnValue(info, v8::String::Empty(info.GetIsolate()));
         return;
     }
-    v8SetReturnValue(info, V8ScriptRunner::callInternalFunction(v8::Handle<v8::Function>::Cast(value), info.This(), 0, 0, info.GetIsolate()));
+    v8::Local<v8::Value> result;
+    if (!V8ScriptRunner::callInternalFunction(v8::Handle<v8::Function>::Cast(value), info.This(), 0, 0, info.GetIsolate()).ToLocal(&result))

[yurys, 2015/03/31 07:20:20]

If we fail to get a valid result there must be a pending exception which the
caller will have to handle. So I wonder what's the reason for bothering to set
any value at all? (I understand that it was written this way before your change
but since you are here it may be a good time to improve this).

[bashi, 2015/04/01 01:51:27]

Changed not to set return value on failure.

+        result = v8::String::Empty(info.GetIsolate());
+    v8SetReturnValue(info, result);
 }
 
 v8::Handle<v8::FunctionTemplate> V8PerIsolateData::toStringTemplate()
 {
     if (m_toStringTemplate.isEmpty())
         m_toStringTemplate.set(isolate(), v8::FunctionTemplate::New(isolate(), constructorOfToString));
     return m_toStringTemplate.newLocal(isolate());
 }
 
 void V8PerIsolateData::addEndOfScopeTask(PassOwnPtr<EndOfScopeTask> task)
@@ skipping 15 matching lines @@
     m_endOfScopeTasks.clear();
 }
 
 void V8PerIsolateData::setScriptDebugServer(PassOwnPtrWillBeRawPtr<ScriptDebugServer> server)
 {
     ASSERT(!m_debugServer);
     m_debugServer = server;
 }
 
 } // namespace blink