Wrap ScreenCapturer with ScreenCapturerDifferWrapper

webrtc/modules/desktop_capture/screen_capturer_win.cc

Index: webrtc/modules/desktop_capture/screen_capturer_win.cc
diff --git a/webrtc/modules/desktop_capture/screen_capturer_win.cc b/webrtc/modules/desktop_capture/screen_capturer_win.cc
index 6a83bec1c522218e039063fa8f3177f6ade71562..6426031a0918a58e6239c0602c37bcc1d3ea6dde 100644
--- a/webrtc/modules/desktop_capture/screen_capturer_win.cc
+++ b/webrtc/modules/desktop_capture/screen_capturer_win.cc
@@ -23,10 +23,10 @@ namespace webrtc {
 // static
 ScreenCapturer* ScreenCapturer::Create(const DesktopCaptureOptions& options) {
   std::unique_ptr<ScreenCapturer> capturer;
-  if (options.allow_directx_capturer() &&
-      ScreenCapturerWinDirectx::IsSupported()) {
-    capturer.reset(new ScreenCapturerWinDirectx(options));
-  } else {
+  if (options.allow_directx_capturer()) {
+    capturer = ScreenCapturerWinDirectx::Create(options);
+  }
+  if (!capturer) {
     capturer.reset(new ScreenCapturerWinGdi(options));
   }