VideoCaptureDeviceFactory: Change device enumeration to callback + QTKit enumerates in UI thread.

media/video/capture/fake_video_capture_device_factory.cc

 // 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.
 
 #include "media/video/capture/fake_video_capture_device_factory.h"
 
 #include "base/strings/stringprintf.h"
 #include "media/video/capture/fake_video_capture_device.h"
 
 namespace media {
 
 FakeVideoCaptureDeviceFactory::FakeVideoCaptureDeviceFactory()
     : number_of_devices_(1) {
 }
 
 scoped_ptr<VideoCaptureDevice> FakeVideoCaptureDeviceFactory::Create(
-    scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner,
     const VideoCaptureDevice::Name& device_name) {
+  DCHECK(thread_checker_.CalledOnValidThread());
   for (int n = 0; n < number_of_devices_; ++n) {
     std::string possible_id = base::StringPrintf("/dev/video%d", n);
     if (device_name.id().compare(possible_id) == 0)
       return scoped_ptr<VideoCaptureDevice>(new FakeVideoCaptureDevice());
   }
   return scoped_ptr<VideoCaptureDevice>();
 }
 
 void FakeVideoCaptureDeviceFactory::GetDeviceNames(
     VideoCaptureDevice::Names* const device_names) {
+  DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(device_names->empty());
   for (int n = 0; n < number_of_devices_; ++n) {
     VideoCaptureDevice::Name name(base::StringPrintf("fake_device_%d", n),
                                   base::StringPrintf("/dev/video%d", n));
     device_names->push_back(name);
   }
 }
 
 void FakeVideoCaptureDeviceFactory::GetDeviceSupportedFormats(
     const VideoCaptureDevice::Name& device,
     VideoCaptureFormats* supported_formats) {
+  DCHECK(thread_checker_.CalledOnValidThread());
   const int frame_rate = 1000 / FakeVideoCaptureDevice::kFakeCaptureTimeoutMs;
   const gfx::Size supported_sizes[] = {gfx::Size(320, 240),
                                        gfx::Size(640, 480),
                                        gfx::Size(1280, 720)};
   supported_formats->clear();
   for (size_t i = 0; i < arraysize(supported_sizes); ++i) {
     supported_formats->push_back(VideoCaptureFormat(supported_sizes[i],
                                                     frame_rate,
                                                     media::PIXEL_FORMAT_I420));
   }
 }
 
 }  // namespace media