This change disables native cursor capture in WgcCapturerWin to better
support the existing idiom of wrapping a capturer in a
DesktopAndCursorComposer. That means we also need to set the top_left
property of output DesktopFrames, so I've also implemented GetTopLeft in
WgcCaptureSource to facilitate this. I've also added a few unit tests
for WgcCaptureSource.
Bug: webrtc:12654
Change-Id: I5c9988a6f8548b584451b073ac29fbb482e09e2e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/215102
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
Commit-Queue: Austin Orion <auorion@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#33821}
