Fix for ~ContentCaptureSubscription() after BrowserThreads are torn down.

content/browser/media/capture/desktop_capture_device_aura.cc

 // Copyright 2013 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.
 
 #include "content/browser/media/capture/desktop_capture_device_aura.h"
 
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/timer/timer.h"
 #include "cc/output/copy_output_request.h"
@@ skipping 209 matching lines @@
 
   power_save_blocker_.reset(PowerSaveBlocker::Create(
       PowerSaveBlocker::kPowerSaveBlockPreventDisplaySleep,
       "DesktopCaptureDevice is running").release());
 
   // Starts timer.
   timer_.Start(FROM_HERE, oracle_proxy_->min_capture_period(),
                base::Bind(&DesktopVideoCaptureMachine::Capture, AsWeakPtr(),
                           false));
 
-  started_ = true;
   return true;
 }
 
 void DesktopVideoCaptureMachine::Stop(const base::Closure& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   power_save_blocker_.reset();
 
   // Stop observing compositor and window events.
   if (desktop_window_) {
     if (desktop_window_->GetHost())
       desktop_window_->GetHost()->compositor()->RemoveObserver(this);
     desktop_window_->RemoveObserver(this);
     desktop_window_ = NULL;
   }
 
   // Stop timer.
   timer_.Stop();
 
-  started_ = false;
-
   callback.Run();
 }
 
 void DesktopVideoCaptureMachine::UpdateCaptureSize() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (oracle_proxy_.get() && desktop_window_) {
     ui::Layer* layer = desktop_window_->layer();
     gfx::Size capture_size =
         ui::ConvertSizeToPixel(layer, layer->bounds().size());
 #if defined(OS_CHROMEOS)
@@ skipping 278 matching lines @@
     scoped_ptr<Client> client) {
   DVLOG(1) << "Allocating " << params.requested_format.frame_size.ToString();
   core_->AllocateAndStart(params, client.Pass());
 }
 
 void DesktopCaptureDeviceAura::StopAndDeAllocate() {
   core_->StopAndDeAllocate();
 }
 
 }  // namespace content