Remove all but one use of WeakPtrFactory::DetachFromThread.

remoting/host/policy_hack/policy_watcher_linux.cc

 // 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.
 
 // Most of this code is copied from various classes in
 // src/chrome/browser/policy. In particular, look at
 //
 //   file_based_policy_loader.{h,cc}
 //   config_dir_policy_provider.{h,cc}
 //
@@ skipping 33 matching lines @@
 
 }  // namespace
 
 class PolicyWatcherLinux : public PolicyWatcher {
  public:
   PolicyWatcherLinux(scoped_refptr<base::SingleThreadTaskRunner> task_runner,
                      const base::FilePath& config_dir)
       : PolicyWatcher(task_runner),
         config_dir_(config_dir),
         weak_factory_(this) {
-    // Detach the factory because we ensure that only the policy thread ever
-    // calls methods on this. Also, the API contract of having to call
-    // StopWatching() (which signals completion) after StartWatching()
-    // before this object can be destructed ensures there are no users of
-    // this object before it is destructed.
-    weak_factory_.DetachFromThread();
   }
 
   virtual ~PolicyWatcherLinux() {}
 
  protected:
   virtual void StartWatchingInternal() OVERRIDE {
     DCHECK(OnPolicyWatcherThread());
     watcher_.reset(new base::FilePathWatcher());
 
     if (!config_dir_.empty() &&
         !watcher_->Watch(
             config_dir_, false,
             base::Bind(&PolicyWatcherLinux::OnFilePathChanged,
                        weak_factory_.GetWeakPtr()))) {
       OnFilePathChanged(config_dir_, true);
     }
 
     // There might have been changes to the directory in the time between
     // construction of the loader and initialization of the watcher. Call reload
     // to detect if that is the case.
     Reload();
 
     ScheduleFallbackReloadTask();
   }
 
   virtual void StopWatchingInternal() OVERRIDE {
     DCHECK(OnPolicyWatcherThread());
-    // Cancel any inflight requests.
+
+    // Stop watching for changes to files in the policies directory.
     watcher_.reset();
+
+    // Orphan any pending OnFilePathChanged tasks.
+    weak_factory_.InvalidateWeakPtrs();
   }
 
  private:
   void OnFilePathChanged(const base::FilePath& path, bool error) {
     DCHECK(OnPolicyWatcherThread());
 
     if (!error)
       Reload();
     else
       LOG(ERROR) << "PolicyWatcherLinux on " << path.value() << " failed.";
@@ skipping 147 matching lines @@
 };
 
 PolicyWatcher* PolicyWatcher::Create(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner) {
   base::FilePath policy_dir(kPolicyDir);
   return new PolicyWatcherLinux(task_runner, policy_dir);
 }
 
 }  // namespace policy_hack
 }  // namespace remoting