CaptureManager: Don't stop a capturer at UnregisterVideoCapturer if it did not start in the first place.
This fixes a bug where, if the VideoCapturer failed to start under certain circumstances, the capture manager would cause a callback saying that the capturer stopped even though it never started in the first place. A VERIFY check in VideoSource::SetState would then cause a crash since the state was set to kEnded when it was already in state kEnded (SetState only allows being called when the state changes).
I only noticed this bug while doing a mistake in a separate CL. Not sure how to reliably reproduce said bug on a working build, but I have previously had camera hardware issues where it couldn't start the camera which resulted in the SetState kEnded -> kEnded crash. Hopefully this will fix that.
R=tommi@webrtc.org
Review URL: https://webrtc-codereview.appspot.com/51039004
Cr-Commit-Position: refs/heads/master@{#9259}
1 file changed
