GitLab

This method simulates occlusion of the CocoaTestHelperWindow
(return value of occlusionState and posting
NSWindowDidChangeOcclusionStateNotification).

Bug: 668690
Change-Id: Ie6acab5d9ec2032dac92e8941b754fb42d45f7db
Reviewed-on: https://chromium-review.googlesource.com/802134
Commit-Queue: François Doray <fdoray@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Reviewed-by: Sidney San Martín <sdy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521787}