[Extensions] Add renderer-side logic to short circuit activity logging

extensions/renderer/user_script_set_manager.h

 // 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.
 
 #ifndef EXTENSIONS_RENDERER_USER_SCRIPT_SET_MANAGER_H_
 #define EXTENSIONS_RENDERER_USER_SCRIPT_SET_MANAGER_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 63 matching lines @@
       content::RenderFrame* render_frame,
       int tab_id,
       UserScript::RunLocation run_location);
 
   // Get active extension IDs from |static_scripts| and each of
   // |programmatic_scripts_|.
   void GetAllActiveExtensionIds(std::set<std::string>* ids) const;
 
   const UserScriptSet* static_scripts() const { return &static_scripts_; }
 
+  void set_activity_logging_enabled(bool enabled) {
+    activity_logging_enabled_ = enabled;
+  }
+
  private:
   // Map for per-extension sets that may be defined programmatically.
   typedef std::map<HostID, linked_ptr<UserScriptSet> > UserScriptSetMap;
 
   // content::RenderThreadObserver implementation.
   bool OnControlMessageReceived(const IPC::Message& message) override;
 
   UserScriptSet* GetProgrammaticScriptsByHostID(const HostID& host_id);
 
   // Handle the UpdateUserScripts extension message.
   void OnUpdateUserScripts(base::SharedMemoryHandle shared_memory,
                            const HostID& host_id,
                            const std::set<HostID>& changed_hosts,
                            bool whitelisted_only);
 
   // Scripts statically defined in extension manifests.
   UserScriptSet static_scripts_;
 
   // Scripts programmatically-defined through API calls (initialized and stored
   // per-extension).
   UserScriptSetMap programmatic_scripts_;
 
+  // Whether or not dom activity should be logged for injected scripts.
+  bool activity_logging_enabled_;
+
   // The associated observers.
   base::ObserverList<Observer> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(UserScriptSetManager);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_USER_SCRIPT_SET_MANAGER_H_