Returns a NULL frame on all platforms if the captured window is closed.
Part of the fix for crbug/360181.
On Mac/Linux, it previously continues capturing even if the window is closed.
Now it stops by returning a NULL frame.
On Windows, it used to stop capturing when the window is minimized. Now fixed to match other platforms.
Note: the crbug still needs a chrome side fix to close the notification bar.
This fix only stops the stream (i.e. stream onended event fired).
BUG=crbug/360181
TESTED=manually tested in Chrome
R=sergeyu@chromium.org
Review URL: https://webrtc-codereview.appspot.com/12329007
git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@5977 4adac7df-926f-26a2-2b94-8c16560cd09d
5 files changed