Per discussion in https://chromium-review.googlesource.com/c/external/webrtc/+/641814, the behavior of IsWindowOnScreen() functions when native APIs fail should be flipped. I.e. window is *not* on screen if OS cannot find it. Bug: chromium:758554 Change-Id: Ife449a5261fcd89c37595e29a0b1802fcf3c42a5 Reviewed-on: https://chromium-review.googlesource.com/644290 Reviewed-by: Jamie Walch <jamiewalch@chromium.org> Commit-Queue: Zijie He <zijiehe@chromium.org> Cr-Commit-Position: refs/heads/master@{#19617}