Change RefPtr<DOMWrapperWorld> that causes reference cycles to DOMWrapperWorld*

Source/bindings/templates/callback_interface.cpp

 {# http://www.chromium.org/blink/coding-style#TOC-License #}
 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 46 matching lines @@
 {% for method in methods if not method.custom %}
 {{method.return_cpp_type}} {{v8_class}}::{{method.name}}({{method.argument_declarations | join(', ')}})
 {
     {% set return_default = 'return true'
            if method.return_idl_type == 'boolean' else 'return' %}{# void #}
     if (!canInvokeCallback())
         {{return_default}};
 
     v8::HandleScope handleScope(m_isolate);
 
-    v8::Handle<v8::Context> v8Context = toV8Context(executionContext(), m_world.get());
+    v8::Handle<v8::Context> v8Context = toV8Context(executionContext(), m_world);
     if (v8Context.IsEmpty())
         {{return_default}};
 
     v8::Context::Scope scope(v8Context);
     {% if method.call_with_this_handle %}
     v8::Handle<v8::Value> thisHandle = thisValue.v8Value();
     if (thisHandle.IsEmpty()) {
         if (!isScriptControllerTerminating())
             CRASH();
         {{return_default}};
@@ skipping 18 matching lines @@
     {% if method.return_idl_type == 'boolean' %}
     return invokeCallback(m_callback.newLocal(m_isolate), {{this_handle_parameter}}{{method.arguments | length}}, argv, executionContext(), m_isolate);
     {% else %}{# void #}
     invokeCallback(m_callback.newLocal(m_isolate), {{this_handle_parameter}}{{method.arguments | length}}, argv, executionContext(), m_isolate);
     {% endif %}
 }
 
 {% endfor %}
 } // namespace WebCore
 {% endfilter %}