base::Bind: Convert FilePathWatcher.

BUG=none
TEST=none

R=willchan@chromium.org

Review URL: http://codereview.chromium.org/8677015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@111405 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: 29ec5c1efd883fcb60d4dd4f4b8f00151c634e9c
diff --git a/base/files/file_path_watcher.cc b/base/files/file_path_watcher.cc
index 7ce64ac..086da1e 100644
--- a/base/files/file_path_watcher.cc
+++ b/base/files/file_path_watcher.cc
@@ -17,6 +17,12 @@
   impl_->Cancel();
 }
 
+// static
+void FilePathWatcher::CancelWatch(
+    const scoped_refptr<PlatformDelegate>& delegate) {
+  delegate->CancelOnMessageLoopThread();
+}
+
 bool FilePathWatcher::Watch(const FilePath& path, Delegate* delegate) {
   DCHECK(path.IsAbsolute());
   return impl_->Watch(path, delegate);
diff --git a/base/files/file_path_watcher.h b/base/files/file_path_watcher.h
index ed17464..9c27ce4 100644
--- a/base/files/file_path_watcher.h
+++ b/base/files/file_path_watcher.h
@@ -40,37 +40,9 @@
     virtual void OnFilePathError(const FilePath& path) {}
   };
 
-  FilePathWatcher();
-  ~FilePathWatcher();
-
-  // Register interest in any changes on |path|. OnPathChanged will be called
-  // back for each change. Returns true on success.
-  // OnFilePathChanged() will be called on the same thread as Watch() is called,
-  // which should have a MessageLoop of TYPE_IO.
-  bool Watch(const FilePath& path, Delegate* delegate) WARN_UNUSED_RESULT;
-
-  class PlatformDelegate;
-
-  // A custom Task that always cleans up the PlatformDelegate, either when
-  // executed or when deleted without having been executed at all, as can
-  // happen during shutdown.
-  class CancelTask : public Task {
-   public:
-    CancelTask(PlatformDelegate* delegate): delegate_(delegate) {}
-    virtual ~CancelTask() {
-      delegate_->CancelOnMessageLoopThread();
-    }
-
-    virtual void Run() OVERRIDE {
-      delegate_->CancelOnMessageLoopThread();
-    }
-   private:
-    scoped_refptr<PlatformDelegate> delegate_;
-
-    DISALLOW_COPY_AND_ASSIGN(CancelTask);
-  };
-
   // Used internally to encapsulate different members on different platforms.
+  // TODO(jhawkins): Move this into its own file. Also fix the confusing naming
+  // wrt Delegate vs PlatformDelegate.
   class PlatformDelegate : public base::RefCountedThreadSafe<PlatformDelegate> {
    public:
     PlatformDelegate();
@@ -85,6 +57,8 @@
     virtual void Cancel() = 0;
 
    protected:
+    friend class FilePathWatcher;
+
     virtual ~PlatformDelegate();
 
     // Stop watching. This is only called on the thread of the appropriate
@@ -111,12 +85,25 @@
 
    private:
     friend class base::RefCountedThreadSafe<PlatformDelegate>;
-    friend class CancelTask;
 
     scoped_refptr<base::MessageLoopProxy> message_loop_;
     bool cancelled_;
   };
 
+  FilePathWatcher();
+  ~FilePathWatcher();
+
+  // A callback that always cleans up the PlatformDelegate, either when executed
+  // or when deleted without having been executed at all, as can happen during
+  // shutdown.
+  static void CancelWatch(const scoped_refptr<PlatformDelegate>& delegate);
+
+  // Register interest in any changes on |path|. OnPathChanged will be called
+  // back for each change. Returns true on success.
+  // OnFilePathChanged() will be called on the same thread as Watch() is called,
+  // which should have a MessageLoop of TYPE_IO.
+  bool Watch(const FilePath& path, Delegate* delegate) WARN_UNUSED_RESULT;
+
  private:
   scoped_refptr<PlatformDelegate> impl_;
 
diff --git a/base/files/file_path_watcher_browsertest.cc b/base/files/file_path_watcher_browsertest.cc
index f48a3b4..f0f789a 100644
--- a/base/files/file_path_watcher_browsertest.cc
+++ b/base/files/file_path_watcher_browsertest.cc
@@ -72,7 +72,7 @@
 
     // Check whether all delegates have been signaled.
     if (signaled_ == delegates_)
-      loop_->PostTask(FROM_HERE, new MessageLoop::QuitTask());
+      loop_->PostTask(FROM_HERE, MessageLoop::QuitClosure());
   }
 
   // Set of registered delegates.
@@ -113,34 +113,14 @@
   DISALLOW_COPY_AND_ASSIGN(TestDelegate);
 };
 
-// A helper class for setting up watches on the file thread.
-class SetupWatchTask : public Task {
- public:
-  SetupWatchTask(const FilePath& target,
-                 FilePathWatcher* watcher,
-                 FilePathWatcher::Delegate* delegate,
-                 bool* result,
-                 base::WaitableEvent* completion)
-      : target_(target),
-        watcher_(watcher),
-        delegate_(delegate),
-        result_(result),
-        completion_(completion) {}
-
-  void Run() {
-    *result_ = watcher_->Watch(target_, delegate_);
-    completion_->Signal();
-  }
-
- private:
-  const FilePath target_;
-  FilePathWatcher* watcher_;
-  FilePathWatcher::Delegate* delegate_;
-  bool* result_;
-  base::WaitableEvent* completion_;
-
-  DISALLOW_COPY_AND_ASSIGN(SetupWatchTask);
-};
+void SetupWatchCallback(const FilePath& target,
+                        FilePathWatcher* watcher,
+                        FilePathWatcher::Delegate* delegate,
+                        bool* result,
+                        base::WaitableEvent* completion) {
+  *result = watcher->Watch(target, delegate);
+  completion->Signal();
+}
 
 class FilePathWatcherTest : public testing::Test {
  public:
@@ -182,12 +162,10 @@
                   FilePathWatcher::Delegate* delegate) WARN_UNUSED_RESULT {
     base::WaitableEvent completion(false, false);
     bool result;
-    file_thread_.message_loop_proxy()->PostTask(FROM_HERE,
-         new SetupWatchTask(target,
-                            watcher,
-                            delegate,
-                            &result,
-                            &completion));
+    file_thread_.message_loop_proxy()->PostTask(
+        FROM_HERE,
+        base::Bind(SetupWatchCallback, target, watcher,
+                   make_scoped_refptr(delegate), &result, &completion));
     completion.Wait();
     return result;
   }
@@ -266,7 +244,7 @@
 
   virtual void OnFilePathChanged(const FilePath& path) {
     watcher_.reset();
-    loop_->PostTask(FROM_HERE, new MessageLoop::QuitTask());
+    loop_->PostTask(FROM_HERE, MessageLoop::QuitClosure());
   }
 
   scoped_ptr<FilePathWatcher> watcher_;
@@ -778,7 +756,7 @@
   // to access the file.
   ASSERT_TRUE(ChangeFilePermissions(test_dir1, Read, false));
   loop_.PostDelayedTask(FROM_HERE,
-                        new MessageLoop::QuitTask,
+                        MessageLoop::QuitClosure(),
                         TestTimeouts::tiny_timeout_ms());
   ASSERT_FALSE(WaitForEvents());
   ASSERT_TRUE(ChangeFilePermissions(test_dir1, Read, true));
diff --git a/base/files/file_path_watcher_linux.cc b/base/files/file_path_watcher_linux.cc
index c9be4ba..86c963c 100644
--- a/base/files/file_path_watcher_linux.cc
+++ b/base/files/file_path_watcher_linux.cc
@@ -412,7 +412,8 @@
   // Switch to the message_loop_ if necessary so we can access |watches_|.
   if (!message_loop()->BelongsToCurrentThread()) {
     message_loop()->PostTask(FROM_HERE,
-                             new FilePathWatcher::CancelTask(this));
+                             base::Bind(&FilePathWatcher::CancelWatch,
+                                        make_scoped_refptr(this)));
   } else {
     CancelOnMessageLoopThread();
   }