[Extensions] Clean up the handling of ExtensionHostMsg_Request

extensions/browser/extension_web_contents_observer.cc

Index: extensions/browser/extension_web_contents_observer.cc
diff --git a/extensions/browser/extension_web_contents_observer.cc b/extensions/browser/extension_web_contents_observer.cc
index 1b1cad86d7336f021af38eacc112b75338a19fd5..779f9a0bc41efd1da05dd7fd5d7ea7535f05caf6 100644
--- a/extensions/browser/extension_web_contents_observer.cc
+++ b/extensions/browser/extension_web_contents_observer.cc
@@ -45,19 +45,33 @@ const Extension* GetExtensionForRenderFrame(
 
 }  // namespace
 
+// static
+ExtensionWebContentsObserver* ExtensionWebContentsObserver::GetForWebContents(
+    content::WebContents* web_contents) {
+  return ExtensionsBrowserClient::Get()->GetExtensionWebContentsObserver(
+      web_contents);
+}
+
 ExtensionWebContentsObserver::ExtensionWebContentsObserver(
     content::WebContents* web_contents)
     : content::WebContentsObserver(web_contents),
-      browser_context_(web_contents->GetBrowserContext()) {
+      browser_context_(web_contents->GetBrowserContext()),
+      dispatcher_(browser_context_) {
   NotifyRenderViewType(web_contents->GetRenderViewHost());
   content::RenderFrameHost* host = web_contents->GetMainFrame();
   if (host)
     RenderFrameHostChanged(nullptr, host);
+  dispatcher_.set_delegate(this);
 }
 
 ExtensionWebContentsObserver::~ExtensionWebContentsObserver() {
 }
 
+content::WebContents* ExtensionWebContentsObserver::GetAssociatedWebContents()
+    const {
+  return web_contents();
+}
+
 void ExtensionWebContentsObserver::RenderViewCreated(
     content::RenderViewHost* render_view_host) {
   NotifyRenderViewType(render_view_host);
@@ -110,6 +124,16 @@ void ExtensionWebContentsObserver::RenderFrameCreated(
   }
 }
 
+bool ExtensionWebContentsObserver::OnMessageReceived(
+    const IPC::Message& message) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(ExtensionWebContentsObserver, message)
+    IPC_MESSAGE_HANDLER(ExtensionHostMsg_Request, OnRequest)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
 void ExtensionWebContentsObserver::FrameDeleted(
     content::RenderFrameHost* render_frame_host) {
   ProcessManager::Get(browser_context_)->UnregisterRenderFrameHost(
@@ -189,4 +213,9 @@ std::string ExtensionWebContentsObserver::GetExtensionId(
   return site.host();
 }
 
+void ExtensionWebContentsObserver::OnRequest(
+    const ExtensionHostMsg_Request_Params& params) {
+  dispatcher_.Dispatch(params, web_contents()->GetRenderViewHost());
+}
+
 }  // namespace extensions