Use factory method to create VideoCaptureDeviceFactory .

media/video/capture/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/video_capture_device_factory.h"
 
 #include "base/command_line.h"
 #include "media/base/media_switches.h"
 #include "media/video/capture/fake_video_capture_device_factory.h"
 #include "media/video/capture/file_video_capture_device_factory.h"
 
-#if defined(OS_MACOSX)
-#include "media/video/capture/mac/video_capture_device_factory_mac.h"
-#elif defined(OS_LINUX)
-#include "media/video/capture/linux/video_capture_device_factory_linux.h"
-#elif defined(OS_ANDROID)
-#include "media/video/capture/android/video_capture_device_factory_android.h"
-#elif defined(OS_WIN)
-#include "media/video/capture/win/video_capture_device_factory_win.h"
-#endif
-
 namespace media {
 
 // static
 scoped_ptr<VideoCaptureDeviceFactory> VideoCaptureDeviceFactory::CreateFactory(
     scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner) {
   const CommandLine* command_line = CommandLine::ForCurrentProcess();
   // Use a Fake or File Video Device Factory if the command line flags are
   // present, otherwise use the normal, platform-dependent, device factory.
   if (command_line->HasSwitch(switches::kUseFakeDeviceForMediaStream)) {
     if (command_line->HasSwitch(switches::kUseFileForFakeVideoCapture)) {
       return scoped_ptr<VideoCaptureDeviceFactory>(new
           media::FileVideoCaptureDeviceFactory());
     } else {
       return scoped_ptr<VideoCaptureDeviceFactory>(new
           media::FakeVideoCaptureDeviceFactory());
     }
   } else {
     // |ui_task_runner| is needed for the Linux ChromeOS factory to retrieve
     // screen rotations and for the Mac factory to run QTKit device enumeration.
-#if defined(OS_MACOSX)
-    return scoped_ptr<VideoCaptureDeviceFactory>(new
-        VideoCaptureDeviceFactoryMac(ui_task_runner));
-#elif defined(OS_LINUX)
-    return scoped_ptr<VideoCaptureDeviceFactory>(new
-        VideoCaptureDeviceFactoryLinux(ui_task_runner));
-#elif defined(OS_ANDROID)
-    return scoped_ptr<VideoCaptureDeviceFactory>(new
-        VideoCaptureDeviceFactoryAndroid());
-#elif defined(OS_WIN)
-    return scoped_ptr<VideoCaptureDeviceFactory>(new
-        VideoCaptureDeviceFactoryWin());
-#else
-    return scoped_ptr<VideoCaptureDeviceFactory>(new
-        VideoCaptureDeviceFactory());
-#endif
+    return scoped_ptr<VideoCaptureDeviceFactory>(
+        CreateVideoCaptureDeviceFactory(ui_task_runner));
   }
 }
 
 VideoCaptureDeviceFactory::VideoCaptureDeviceFactory() {
   thread_checker_.DetachFromThread();
 }
 
 VideoCaptureDeviceFactory::~VideoCaptureDeviceFactory() {}
 
 void VideoCaptureDeviceFactory::EnumerateDeviceNames(const base::Callback<
     void(scoped_ptr<media::VideoCaptureDevice::Names>)>& callback) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(!callback.is_null());
   scoped_ptr<VideoCaptureDevice::Names> device_names(
       new VideoCaptureDevice::Names());
   GetDeviceNames(device_names.get());
   callback.Run(device_names.Pass());
 }
 
+#if !defined(OS_MACOSX) && !defined(OS_LINUX) && !defined(OS_ANDROID) && !defined(OS_WIN)
+// static
+VideoCaptureDeviceFactory*
+VideoCaptureDeviceFactory::CreateVideoCaptureDeviceFactory(
+    scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner) {
+  NOTIMPLEMENTED();
+  return NULL;
+}
+#endif
+
 }  // namespace media