Bug 1676760 - Remove unused RefreshTimerVsyncDispatcher::SetParentRef…

…reshTimer. r=smaug

Even in the parent process, VsyncRefreshDriverTimer uses AddChildRefreshTimer.

Differential Revision: https://phabricator.services.mozilla.com/D139768

gfx/tests/gtest/TestVsync.cpp

@@ -136,36 +136,6 @@ TEST_F(VsyncTester, CompositorGetVsyncNotifications) {
   ASSERT_FALSE(globalDisplay.IsVsyncEnabled());
 }
 
-// Test that if we have vsync enabled, the parent refresh driver should get
-// notifications
-TEST_F(VsyncTester, ParentRefreshDriverGetVsyncNotifications) {
-  VsyncSource::Display& globalDisplay = mVsyncSource->GetGlobalDisplay();
-  globalDisplay.DisableVsync();
-  ASSERT_FALSE(globalDisplay.IsVsyncEnabled());
-
-  RefPtr<RefreshTimerVsyncDispatcher> vsyncDispatcher =
-      globalDisplay.GetRefreshTimerVsyncDispatcher();
-  ASSERT_TRUE(vsyncDispatcher != nullptr);
-
-  RefPtr<TestVsyncObserver> testVsyncObserver = new TestVsyncObserver();
-  vsyncDispatcher->SetParentRefreshTimer(testVsyncObserver);
-  ASSERT_TRUE(globalDisplay.IsVsyncEnabled());
-
-  testVsyncObserver->WaitForVsyncNotification();
-  ASSERT_TRUE(testVsyncObserver->DidGetVsyncNotification());
-  vsyncDispatcher->SetParentRefreshTimer(nullptr);
-
-  testVsyncObserver->ResetVsyncNotification();
-  testVsyncObserver->WaitForVsyncNotification();
-  ASSERT_FALSE(testVsyncObserver->DidGetVsyncNotification());
-
-  vsyncDispatcher = nullptr;
-  testVsyncObserver = nullptr;
-
-  globalDisplay.DisableVsync();
-  ASSERT_FALSE(globalDisplay.IsVsyncEnabled());
-}
-
 // Test that child refresh vsync observers get vsync notifications
 TEST_F(VsyncTester, ChildRefreshDriverGetVsyncNotifications) {
   VsyncSource::Display& globalDisplay = mVsyncSource->GetGlobalDisplay();

widget/VsyncDispatcher.cpp

@@ -134,22 +134,6 @@ void RefreshTimerVsyncDispatcher::NotifyVsync(const VsyncEvent& aVsync) {
   for (size_t i = 0; i < mChildRefreshTimers.Length(); i++) {
     mChildRefreshTimers[i]->NotifyVsync(aVsync);
   }
-
-  if (mParentRefreshTimer) {
-    mParentRefreshTimer->NotifyVsync(aVsync);
-  }
-}
-
-void RefreshTimerVsyncDispatcher::SetParentRefreshTimer(
-    VsyncObserver* aVsyncObserver) {
-  MOZ_ASSERT(NS_IsMainThread());
-  {  // lock scope because UpdateVsyncStatus runs on main thread and will
-     // deadlock
-    MutexAutoLock lock(mRefreshTimersLock);
-    mParentRefreshTimer = aVsyncObserver;
-  }
-
-  UpdateVsyncStatus();
 }
 
 void RefreshTimerVsyncDispatcher::AddChildRefreshTimer(
@@ -190,7 +174,7 @@ void RefreshTimerVsyncDispatcher::UpdateVsyncStatus() {
 bool RefreshTimerVsyncDispatcher::NeedsVsync() {
   MOZ_ASSERT(NS_IsMainThread());
   MutexAutoLock lock(mRefreshTimersLock);
-  return (mParentRefreshTimer != nullptr) || !mChildRefreshTimers.IsEmpty();
+  return !mChildRefreshTimers.IsEmpty();
 }
 
 }  // namespace mozilla

widget/VsyncDispatcher.h

@@ -81,10 +81,6 @@ class RefreshTimerVsyncDispatcher final {
 
   void MoveToDisplay(gfx::VsyncSource::Display* aDisplay);
 
-  // Set chrome process's RefreshTimer to this dispatcher.
-  // This function can be called from any thread.
-  void SetParentRefreshTimer(VsyncObserver* aVsyncObserver);
-
   // Add or remove the content process' RefreshTimer to this dispatcher. This
   // will be a no-op for AddChildRefreshTimer() if the observer is already
   // registered.
@@ -102,7 +98,6 @@ class RefreshTimerVsyncDispatcher final {
   // hold a RefPtr back without causing a cyclic dependency.
   gfx::VsyncSource::Display* mDisplay;
   Mutex mRefreshTimersLock;
-  RefPtr<VsyncObserver> mParentRefreshTimer;
   nsTArray<RefPtr<VsyncObserver>> mChildRefreshTimers;
 };