[Extensions] Clean up the handling of ExtensionHostMsg_Request

extensions/browser/guest_view/extension_options/extension_options_guest.cc

Index: extensions/browser/guest_view/extension_options/extension_options_guest.cc
diff --git a/extensions/browser/guest_view/extension_options/extension_options_guest.cc b/extensions/browser/guest_view/extension_options/extension_options_guest.cc
index c88231570cf50734e730f16d5a8702ffa68b0622..339906adf846dfa00dad7ec9dcda7f4b1236bbd7 100644
--- a/extensions/browser/guest_view/extension_options/extension_options_guest.cc
+++ b/extensions/browser/guest_view/extension_options/extension_options_guest.cc
@@ -17,7 +17,6 @@
 #include "extensions/browser/bad_message.h"
 #include "extensions/browser/extension_function_dispatcher.h"
 #include "extensions/browser/extension_registry.h"
-#include "extensions/browser/extension_web_contents_observer.h"
 #include "extensions/browser/guest_view/extension_options/extension_options_constants.h"
 #include "extensions/browser/guest_view/extension_options/extension_options_guest_delegate.h"
 #include "extensions/common/api/extension_options_internal.h"
@@ -117,11 +116,7 @@ void ExtensionOptionsGuest::CreateWebContents(
 
 void ExtensionOptionsGuest::DidInitialize(
     const base::DictionaryValue& create_params) {
-  extension_function_dispatcher_.reset(
-      new extensions::ExtensionFunctionDispatcher(browser_context(), this));
-  if (extension_options_guest_delegate_) {
-    extension_options_guest_delegate_->DidInitialize();
-  }
+  ExtensionsAPIClient::Get()->AttachWebContentsHelpers(web_contents());
   web_contents()->GetController().LoadURL(options_page_,
                                           content::Referrer(),
                                           ui::PAGE_TRANSITION_LINK,
@@ -160,10 +155,6 @@ void ExtensionOptionsGuest::OnPreferredSizeChanged(const gfx::Size& pref_size) {
       options.ToValue()));
 }
 
-content::WebContents* ExtensionOptionsGuest::GetAssociatedWebContents() const {
-  return web_contents();
-}
-
 content::WebContents* ExtensionOptionsGuest::OpenURLFromTab(
     content::WebContents* source,
     const content::OpenURLParams& params) {
@@ -244,19 +235,4 @@ void ExtensionOptionsGuest::DidNavigateMainFrame(
   }
 }
 
-bool ExtensionOptionsGuest::OnMessageReceived(const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(ExtensionOptionsGuest, message)
-    IPC_MESSAGE_HANDLER(ExtensionHostMsg_Request, OnRequest)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
-
-void ExtensionOptionsGuest::OnRequest(
-    const ExtensionHostMsg_Request_Params& params) {
-  extension_function_dispatcher_->Dispatch(params,
-                                           web_contents()->GetRenderViewHost());
-}
-
 }  // namespace extensions