[Extensions Bindings] Request JS execution from messaging bindings

extensions/shell/renderer/shell_extensions_renderer_client.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/shell/renderer/shell_extensions_renderer_client.h"
 
+#include "base/memory/ptr_util.h"
+#include "extensions/renderer/dispatcher.h"
+#include "extensions/renderer/dispatcher_delegate.h"
+
 namespace extensions {
 
-ShellExtensionsRendererClient::ShellExtensionsRendererClient() {
-}
+ShellExtensionsRendererClient::ShellExtensionsRendererClient()
+    : dispatcher_delegate_(base::MakeUnique<DispatcherDelegate>()),
+      dispatcher_(base::MakeUnique<Dispatcher>(dispatcher_delegate_.get())) {}
 
 ShellExtensionsRendererClient::~ShellExtensionsRendererClient() {
 }
 
 bool ShellExtensionsRendererClient::IsIncognitoProcess() const {
   // app_shell doesn't support off-the-record contexts.
   return false;
 }
 
 int ShellExtensionsRendererClient::GetLowestIsolatedWorldId() const {
   // app_shell doesn't need to reserve world IDs for anything other than
   // extensions, so we always return 1. Note that 0 is reserved for the global
   // world.
   return 1;
 }
 
+Dispatcher* ShellExtensionsRendererClient::GetDispatcher() {
+  return dispatcher_.get();
+}
+
 }  // namespace extensions