Get rid of MessageLoop* caching in extensions code.

chrome/browser/extensions/user_script_master.h

 // Copyright (c) 2008 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_BROWSER_EXTENSIONS_USER_SCRIPT_MASTER_H_
 #define CHROME_BROWSER_EXTENSIONS_USER_SCRIPT_MASTER_H_
 
 #include <vector>
 
 #include "base/directory_watcher.h"
 #include "base/file_path.h"
 #include "base/scoped_ptr.h"
 #include "base/shared_memory.h"
+#include "chrome/browser/chrome_thread.h"
 #include "chrome/common/extensions/user_script.h"
 #include "chrome/common/notification_registrar.h"
 #include "testing/gtest/include/gtest/gtest_prod.h"
 
-class MessageLoop;
 namespace base {
 class StringPiece;
 }
 
 // Manages a segment of shared memory that contains the user scripts the user
 // has installed.  Lives on the UI thread.
 class UserScriptMaster : public base::RefCountedThreadSafe<UserScriptMaster>,
                          public DirectoryWatcher::Delegate,
                          public NotificationObserver {
  public:
-  // For testability, the constructor takes the MessageLoop to run the
-  // script-reloading worker on as well as the path the scripts live in.
-  // These are normally the file thread and a directory inside the profile.
-  UserScriptMaster(MessageLoop* worker, const FilePath& script_dir);
+  // For testability, the constructor takes the path the scripts live in.
+  // This is normally a directory inside the profile.
+  UserScriptMaster(const FilePath& script_dir);
   virtual ~UserScriptMaster();
 
   // Add a watched directory. All scripts will be reloaded when any file in
   // this directory changes.
   void AddWatchedPath(const FilePath& path);
 
   // Kicks off a process on the file thread to reload scripts from disk
   // into a new chunk of shared memory and notify renderers.
   virtual void StartScan();
 
@@ skipping 32 matching lines @@
     static bool ParseMetadataHeader(const base::StringPiece& script_text,
                                     UserScript* script);
 
     static void LoadScriptsFromDirectory(const FilePath& script_dir,
                                          UserScriptList* result);
 
     explicit ScriptReloader(UserScriptMaster* master);
 
     // Start a scan for scripts.
     // Will always send a message to the master upon completion.
-    void StartScan(MessageLoop* work_loop, const FilePath& script_dir,
+    void StartScan(const FilePath& script_dir,
                    const UserScriptList& external_scripts);
 
     // The master is going away; don't call it back.
     void DisownMaster() {
       master_ = NULL;
     }
 
    private:
     // Where functions are run:
     //    master          file
@@ skipping 11 matching lines @@
     // done. The parameters are intentionally passed by value so their lifetimes
     // aren't tied to the caller.
     void RunScan(const FilePath script_dir, UserScriptList lone_scripts);
 
     // A pointer back to our master.
     // May be NULL if DisownMaster() is called.
     UserScriptMaster* master_;
 
     // The message loop to call our master back on.
     // Expected to always outlive us.
-    MessageLoop* master_message_loop_;
+    ChromeThread::ID master_thread_id_;
 
     DISALLOW_COPY_AND_ASSIGN(ScriptReloader);
   };
 
   // DirectoryWatcher::Delegate implementation.
   virtual void OnDirectoryChanged(const FilePath& path);
 
   // NotificationObserver implementation.
   virtual void Observe(NotificationType type,
                        const NotificationSource& source,
                        const NotificationDetails& details);
 
   // Manages our notification registrations.
   NotificationRegistrar registrar_;
 
   // The directories containing user scripts.
   FilePath user_script_dir_;
 
   // The watcher watches the profile's user scripts directory for new scripts.
   std::vector<DirectoryWatcher*> dir_watchers_;
 
-  // The MessageLoop that the scanner worker runs on.
-  // Typically the file thread; configurable for testing.
-  MessageLoop* worker_loop_;
-
   // ScriptReloader (in another thread) reloads script off disk.
   // We hang on to our pointer to know if we've already got one running.
   scoped_refptr<ScriptReloader> script_reloader_;
 
   // Contains the scripts that were found the last time scripts were updated.
   scoped_ptr<base::SharedMemory> shared_memory_;
 
   // List of scripts outside of script directories we should also load.
   UserScriptList lone_scripts_;
 
   // If the extensions service has finished loading its initial set of
   // extensions.
   bool extensions_service_ready_;
 
   // If the script directory is modified while we're rescanning it, we note
   // that we're currently mid-scan and then start over again once the scan
   // finishes.  This boolean tracks whether another scan is pending.
   bool pending_scan_;
 
   DISALLOW_COPY_AND_ASSIGN(UserScriptMaster);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_USER_SCRIPT_MASTER_H_