Use FrameTreeNode ID as frameId in extension APIs

extensions/browser/extension_web_contents_observer.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/browser/extension_web_contents_observer.h"
 
 #include "content/public/browser/child_process_security_policy.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/site_instance.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/url_constants.h"
+#include "extensions/browser/extension_api_frame_id_map.h"
 #include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extensions_browser_client.h"
 #include "extensions/browser/mojo/service_registration.h"
 #include "extensions/browser/process_manager.h"
 #include "extensions/browser/view_type_utils.h"
 #include "extensions/common/constants.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_messages.h"
 #include "extensions/common/view_type.h"
@@ skipping 78 matching lines @@
   // refactoring this isn't trivial to do, and this way is simpler.
   //
   // Plus, we can delete the concept of activating an extension once site
   // isolation is turned on.
   render_view_host->Send(new ExtensionMsg_ActivateExtension(extension->id()));
 }
 
 void ExtensionWebContentsObserver::RenderFrameCreated(
     content::RenderFrameHost* render_frame_host) {
   InitializeRenderFrame(render_frame_host);
+
+  // Optimization: Look up the extension API frame ID to force the mapping to be
+  // cached. This minimizes the number of IO->UI->IO thread hops when the ID is
+  // looked up again on the IO thread for the webRequest API.
+  ExtensionApiFrameIdMap::Get()->CacheFrameId(render_frame_host);
 }
 
 void ExtensionWebContentsObserver::RenderFrameDeleted(
     content::RenderFrameHost* render_frame_host) {
   ProcessManager::Get(browser_context_)
       ->UnregisterRenderFrameHost(render_frame_host);
+  ExtensionApiFrameIdMap::Get()->RemoveFrameId(render_frame_host);
 }
 
 void ExtensionWebContentsObserver::DidCommitProvisionalLoadForFrame(
     content::RenderFrameHost* render_frame_host,
     const GURL& url,
     ui::PageTransition transition_type) {
   ProcessManager* pm = ProcessManager::Get(browser_context_);
 
   if (pm->IsRenderFrameHostRegistered(render_frame_host)) {
     const Extension* frame_extension =
@@ skipping 143 matching lines @@
   // Since this is called for all existing RenderFrameHosts during the
   // ExtensionWebContentsObserver's creation, it's possible that not all hosts
   // are ready.
   // We only initialize the frame if the renderer counterpart is live; otherwise
   // we wait for the RenderFrameCreated notification.
   if (render_frame_host->IsRenderFrameLive())
     InitializeRenderFrame(render_frame_host);
 }
 
 }  // namespace extensions