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

media/video/capture/linux/video_capture_device_factory_linux.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/linux/video_capture_device_factory_linux.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #if defined(OS_OPENBSD)
 #include <sys/videoio.h>
@@ skipping 26 matching lines @@
   while (HANDLE_EINTR(ioctl(fd, VIDIOC_ENUM_FMT, &fmtdesc)) == 0) {
     if (std::find(usable_fourccs.begin(), usable_fourccs.end(),
                   fmtdesc.pixelformat) != usable_fourccs.end())
       return true;
 
     fmtdesc.index++;
   }
   return false;
 }
 
+VideoCaptureDeviceFactoryLinux::VideoCaptureDeviceFactoryLinux(
+    scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner)
+    : ui_task_runner_(ui_task_runner) {
+}
+
+VideoCaptureDeviceFactoryLinux::~VideoCaptureDeviceFactoryLinux() {
+}
+
 scoped_ptr<VideoCaptureDevice> VideoCaptureDeviceFactoryLinux::Create(
-    scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner,
     const VideoCaptureDevice::Name& device_name) {
   DCHECK(thread_checker_.CalledOnValidThread());
 #if defined(OS_CHROMEOS)
   VideoCaptureDeviceChromeOS* self =
-      new VideoCaptureDeviceChromeOS(ui_task_runner, device_name);
+      new VideoCaptureDeviceChromeOS(ui_task_runner_, device_name);
 #else
   VideoCaptureDeviceLinux* self = new VideoCaptureDeviceLinux(device_name);
 #endif
   if (!self)
     return scoped_ptr<VideoCaptureDevice>();
   // Test opening the device driver. This is to make sure it is available.
   // We will reopen it again in our worker thread when someone
   // allocates the camera.
   base::ScopedFD fd(HANDLE_EINTR(open(device_name.id().c_str(), O_RDONLY)));
   if (!fd.is_valid()) {
@@ skipping 107 matching lines @@
         ++frame_interval.index;
       }
       ++frame_size.index;
     }
     ++pixel_format.index;
   }
   return;
 }
 
 }  // namespace media