GitLab

This reverts commit f34c7c2b.

Reason for revert:
Likely culprit for frequent test flakes on win7 dbg bot.
Sample failing build: https://ci.chromium.org/p/chromium/builders/ci/Win7%20Tests%20%28dbg%29%281%29
Sample failure stack:
[1744:6088:1218/071720.166:FATAL:native_window_occlusion_tracker_win.cc(420)] Check failed: FALSE. A root window did not get its occlusion state set
Backtrace:
	base::debug::CollectStackTrace [0x6F2A256C+60] (o:\base\debug\stack_trace_win.cc:284)
	base::debug::StackTrace::StackTrace [0x6EFAA18E+78] (o:\base\debug\stack_trace.cc:206)
	base::debug::StackTrace::StackTrace [0x6EFAA102+34] (o:\base\debug\stack_trace.cc:203)
	logging::LogMessage::~LogMessage [0x6EFE9AC0+144] (o:\base\logging.cc:628)
	aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::ComputeNativeWindowOcclusionStatus [0x647E0ADC+1660] (o:\ui\aura\native_window_occlusion_tracker_win.cc:418)
	base::internal::FunctorTraits<void (aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::*)() __attribute__((thiscall)),void>::Invoke<void (aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::*)() __attribute__((thiscall)),aura: [0x647F372C+28] (o:\base\bind_internal.h:498)
	base::internal::InvokeHelper<0,void>::MakeItSo<void (aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::*)() __attribute__((thiscall)),aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator *> [0x647F369F+79] (o:\base\bind_internal.h:598)
	base::internal::Invoker<base::internal::BindState<void (aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::*)() __attribute__((thiscall)),base::internal::UnretainedWrapper<aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator> >, [0x647F35F5+85] (o:\base\bind_internal.h:671)
	base::internal::Invoker<base::internal::BindState<void (aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::*)() __attribute__((thiscall)),base::internal::UnretainedWrapper<aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator> >, [0x647F3584+84] (o:\base\bind_internal.h:640)
	base::OnceCallback<void ()>::Run [0x6EF62360+80] (o:\base\callback.h:99)
	base::OneShotTimer::RunUserTask [0x6F1F8DB9+265] (o:\base\timer\timer.cc:265)
	base::internal::TimerBase::RunScheduledTask [0x6F1F88D5+293] (o:\base\timer\timer.cc:227)
	base::internal::BaseTimerTaskInternal::Run [0x6F1F875C+60] (o:\base\timer\timer.cc:50)
	base::internal::FunctorTraits<void (base::internal::BaseTimerTaskInternal::*)() __attribute__((thiscall)),void>::Invoke<void (base::internal::BaseTimerTaskInternal::*)() __attribute__((thiscall)),base::internal::BaseTimerTaskInternal *> [0x6F1F9CAC+28] (o:\base\bind_internal.h:498)
	base::internal::InvokeHelper<0,void>::MakeItSo<void (base::internal::BaseTimerTaskInternal::*)() __attribute__((thiscall)),base::internal::BaseTimerTaskInternal *> [0x6F1F9C0F+79] (o:\base\bind_internal.h:598)
	base::internal::Invoker<base::internal::BindState<void (base::internal::BaseTimerTaskInternal::*)() __attribute__((thiscall)),base::internal::OwnedWrapper<base::internal::BaseTimerTaskInternal> >,void ()>::RunImpl<void (base::internal::BaseTimerTaskIntern [0x6F1F9B65+85] (o:\base\bind_internal.h:671)
	base::internal::Invoker<base::internal::BindState<void (base::internal::BaseTimerTaskInternal::*)() __attribute__((thiscall)),base::internal::OwnedWrapper<base::internal::BaseTimerTaskInternal> >,void ()>::RunOnce [0x6F1F9AF4+84] (o:\base\bind_internal.h:640)
	base::OnceCallback<void ()>::Run [0x6EF62360+80] (o:\base\callback.h:99)
	base::TaskAnnotator::RunTask [0x6F116BF7+1447] (o:\base\task\common\task_annotator.cc:144)
	base::internal::TaskTracker::RunSkipOnShutdown [0x6F1A354D+61] (o:\base\task\thread_pool\task_tracker.cc:778)
	base::internal::TaskTracker::RunTaskWithShutdownBehavior [0x6F1A2C1C+108] (o:\base\task\thread_pool\task_tracker.cc:796)
	base::internal::TaskTracker::RunTask [0x6F1A2289+2521] (o:\base\task\thread_pool\task_tracker.cc:639)
	base::internal::TaskTracker::RunAndPopNextTask [0x6F1A0FA6+598] (o:\base\task\thread_pool\task_tracker.cc:512)
	base::internal::WorkerThread::RunWorker [0x6F1C47CE+2270] (o:\base\task\thread_pool\worker_thread.cc:321)
	base::internal::WorkerThread::RunSharedCOMWorker [0x6F1C3E92+34] (o:\base\task\thread_pool\worker_thread.cc:261)
	base::internal::WorkerThread::ThreadMain [0x6F1C3C3A+250] (o:\base\task\thread_pool\worker_thread.cc:213)
	base::`anonymous namespace'::ThreadFunc [0x6F2CCF4D+301] (o:\base\threading\platform_thread_win.cc:112)
	BaseThreadInitThunk [0x7740343D+18]
	RtlInitializeExceptionChain [0x77919802+99]
	RtlInitializeExceptionChain [0x779197D5+54]
Task trace:
Backtrace:
	aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::ScheduleOcclusionCalculationIfNeeded [0x647DF4F2+290] (o:\ui\aura\native_window_occlusion_tracker_win.cc:433)
	aura::NativeWindowOcclusionTrackerWin::WindowOcclusionCalculator::ProcessEventHookCallback [0x647DFBB4+324] (o:\ui\aura\native_window_occlusion_tracker_win.cc:600)

Original change's description:
> Use unoccluded desktop region to calculate root window occlusion.
> 
> Bug: 1029842
> Change-Id: I285c8dec077575ce246c476645e2ff4a3294124c
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1951775
> Commit-Queue: David Bienvenu <davidbienvenu@chromium.org>
> Reviewed-by: François Doray <fdoray@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#725750}

TBR=chrisha@chromium.org,fdoray@chromium.org,davidbienvenu@chromium.org

Change-Id: I3de865e1e2bfbc0178f117ff5756394b52f1de88
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1029842
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1974052Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#725993}