Take 2 at implementing activeTab.

chrome/renderer/extensions/extension_dispatcher.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_RENDERER_EXTENSIONS_EXTENSION_DISPATCHER_H_
 #define CHROME_RENDERER_EXTENSIONS_EXTENSION_DISPATCHER_H_
 #pragma once
 
 #include <set>
 #include <string>
@@ skipping 135 matching lines @@
   void OnSetScriptingWhitelist(
       const extensions::Extension::ScriptingWhitelist& extension_ids);
   void OnPageActionsUpdated(const std::string& extension_id,
       const std::vector<std::string>& page_actions);
   void OnActivateExtension(const std::string& extension_id);
   void OnUpdatePermissions(int reason_id,
                            const std::string& extension_id,
                            const ExtensionAPIPermissionSet& apis,
                            const URLPatternSet& explicit_hosts,
                            const URLPatternSet& scriptable_hosts);
+  void OnUpdateTabSpecificPermissions(int page_id,
+                                      int tab_id,
+                                      const std::string& extension_id,
+                                      const URLPatternSet& origin_set);
+  void OnClearTabSpecificPermissions(
+      int tab_id,
+      const std::vector<std::string>& extension_ids);
   void OnUpdateUserScripts(base::SharedMemoryHandle table);
   void OnUsingWebRequestAPI(
       bool adblock,
       bool adblock_plus,
       bool other_webrequest);
   void OnShouldUnload(const std::string& extension_id, int sequence_id);
   void OnUnload(const std::string& extension_id);
 
   // Update the list of active extensions that will be reported when we crash.
   void UpdateActiveExtensions();
 
   // Calls RenderThread's RegisterExtension and keeps tracks of which v8
   // extension is for Chrome Extensions only.
   void RegisterExtension(v8::Extension* extension, bool restrict_to_extensions);
 
   // Sets up the host permissions for |extension|.
   void InitOriginPermissions(const extensions::Extension* extension);
-  void UpdateOriginPermissions(
+  void AddOrRemoveOriginPermissions(
       extensions::UpdatedExtensionPermissionsInfo::Reason reason,
       const extensions::Extension* extension,
       const URLPatternSet& origins);
 
   void RegisterNativeHandlers(ModuleSystem* module_system,
                               ChromeV8Context* context);
 
   // Inserts static source code into |source_map_|.
   void PopulateSourceMap();
 
@@ skipping 60 matching lines @@
   scoped_ptr<ExtensionRequestSender> request_sender_;
 
   // The current channel. From VersionInfo::GetChannel().
   // TODO(aa): Remove when we can restrict non-permission APIs to dev-only.
   int chrome_channel_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionDispatcher);
 };
 
 #endif  // CHROME_RENDERER_EXTENSIONS_EXTENSION_DISPATCHER_H_