Query the preferred readback config in CopyFromBackingStore

content/browser/media/capture/web_contents_video_capture_device.cc

Index: content/browser/media/capture/web_contents_video_capture_device.cc
diff --git a/content/browser/media/capture/web_contents_video_capture_device.cc b/content/browser/media/capture/web_contents_video_capture_device.cc
index 093703e145c051b790873ae35219ea0e7fab8114..75f0e9f56bd9389232ef291f2ebadc29c90ff752 100644
--- a/content/browser/media/capture/web_contents_video_capture_device.cc
+++ b/content/browser/media/capture/web_contents_video_capture_device.cc
@@ -666,12 +666,16 @@ void WebContentsCaptureMachine::Capture(
                    weak_ptr_factory_.GetWeakPtr(),
                    start_time, deliver_frame_cb));
   } else {
+    SkBitmap::Config preffered_format = rwh->PreferredReadbackFormat();

[piman, 2014/03/10 18:27:20]

typo: preferred_format

[sivag, 2014/03/11 14:41:50]

Done.

     rwh->CopyFromBackingStore(
         gfx::Rect(),
         fitted_size,  // Size here is a request not always honored.
         base::Bind(&WebContentsCaptureMachine::DidCopyFromBackingStore,
                    weak_ptr_factory_.GetWeakPtr(),
-                   start_time, target, deliver_frame_cb));
+                   start_time,
+                   target,
+                   deliver_frame_cb),
+        preffered_format);

[piman, 2014/03/10 18:27:20]

The receiving code only accepts RGBA8888, see RenderVideoFrame. So we can't
blindly use the preferred format, we should force it to 8888.

[sivag, 2014/03/11 14:41:50]

Done.

   }
 }