Bug 1741799 - Remove SupportsThreadSafeWeakPtr from WinWindowOcclusionTracker r=nical,gfx-reviewers

SupportsThreadSafeWeakPtr is not necessary for current WinWindowOcclusionTracker.

Differential Revision: https://phabricator.services.mozilla.com/D131469

widget/windows/WinWindowOcclusionTracker.cpp

@@ -86,16 +86,16 @@ class OcclusionUpdateRunnable : public CancelableRunnable {
 
 class UpdateOcclusionStateRunnable : public Runnable {
  public:
-  UpdateOcclusionStateRunnable(
-      ThreadSafeWeakPtr<WinWindowOcclusionTracker> aOcclusionTracker,
-      std::unordered_map<HWND, OcclusionState>* aMap, bool aShowAllWindows)
+  UpdateOcclusionStateRunnable(std::unordered_map<HWND, OcclusionState>* aMap,
+                               bool aShowAllWindows)
       : Runnable("UpdateOcclusionStateRunnable"),
-        mOcclusionTracker(aOcclusionTracker),
         mMap(aMap),
         mShowAllWindows(aShowAllWindows) {}
 
   NS_IMETHOD Run() override {
-    auto tracker = RefPtr<WinWindowOcclusionTracker>(mOcclusionTracker);
+    MOZ_ASSERT(NS_IsMainThread());
+
+    auto* tracker = WinWindowOcclusionTracker::Get();
     if (tracker) {
       tracker->UpdateOcclusionState(mMap, mShowAllWindows);
     }
@@ -103,7 +103,6 @@ class UpdateOcclusionStateRunnable : public Runnable {
   }
 
  private:
-  ThreadSafeWeakPtr<WinWindowOcclusionTracker> mOcclusionTracker;
   std::unordered_map<HWND, OcclusionState>* const mMap;
   const bool mShowAllWindows;
 };
@@ -334,7 +333,7 @@ already_AddRefed<SerializedRunnable> SerializedTaskDispatcher::GetNextTask(
 StaticRefPtr<WinWindowOcclusionTracker> WinWindowOcclusionTracker::sTracker;
 
 /* static */
-RefPtr<WinWindowOcclusionTracker> WinWindowOcclusionTracker::Get() {
+WinWindowOcclusionTracker* WinWindowOcclusionTracker::Get() {
   MOZ_ASSERT(NS_IsMainThread());
   return sTracker;
 }
@@ -762,9 +761,8 @@ WinWindowOcclusionTracker::WindowOcclusionCalculator::
   MOZ_ASSERT(NS_IsMainThread());
   LOG(LogLevel::Info, "WindowOcclusionCalculator()");
 
-  auto tracker = WinWindowOcclusionTracker::Get();
-  mSerializedTaskDispatcher = tracker->GetSerializedTaskDispatcher();
-  mOcclusionTracker = ThreadSafeWeakPtr<WinWindowOcclusionTracker>(tracker);
+  mSerializedTaskDispatcher =
+      WinWindowOcclusionTracker::Get()->GetSerializedTaskDispatcher();
 }
 
 WinWindowOcclusionTracker::WindowOcclusionCalculator::
@@ -989,7 +987,7 @@ void WinWindowOcclusionTracker::WindowOcclusionCalculator::
   }
 
   RefPtr<Runnable> runnable = new UpdateOcclusionStateRunnable(
-      mOcclusionTracker, &mRootWindowHwndsOcclusionState, mShowingThumbnails);
+      &mRootWindowHwndsOcclusionState, mShowingThumbnails);
   mSerializedTaskDispatcher->PostTaskToMain(runnable.forget());
 }
 
@@ -1205,8 +1203,7 @@ void WinWindowOcclusionTracker::WindowOcclusionCalculator::
         mShowingThumbnails = true;
 
         RefPtr<Runnable> runnable = new UpdateOcclusionStateRunnable(
-            mOcclusionTracker, &mRootWindowHwndsOcclusionState,
-            mShowingThumbnails);
+            &mRootWindowHwndsOcclusionState, mShowingThumbnails);
         mSerializedTaskDispatcher->PostTaskToMain(runnable.forget());
       }
     }

widget/windows/WinWindowOcclusionTracker.h

@@ -39,16 +39,13 @@ class UpdateOcclusionStateRunnable;
 
 // This class handles window occlusion tracking by using HWND.
 // Implementation is borrowed from chromium's NativeWindowOcclusionTrackerWin.
-class WinWindowOcclusionTracker final
-    : public SupportsThreadSafeWeakPtr<WinWindowOcclusionTracker>,
-      public DisplayStatusListener,
+class WinWindowOcclusionTracker final : public DisplayStatusListener,
                                         public SessionChangeListener {
  public:
-  MOZ_DECLARE_THREADSAFEWEAKREFERENCE_TYPENAME(WinWindowOcclusionTracker)
-  MOZ_DECLARE_REFCOUNTED_TYPENAME(WinWindowOcclusionTracker)
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(WinWindowOcclusionTracker)
 
   /// Can only be called from the main thread.
-  static RefPtr<WinWindowOcclusionTracker> Get();
+  static WinWindowOcclusionTracker* Get();
 
   /// Can only be called from the main thread.
   static void Ensure();
@@ -62,8 +59,6 @@ class WinWindowOcclusionTracker final
   /// Can be called from any thread.
   static bool IsInWinWindowOcclusionThread();
 
-  virtual ~WinWindowOcclusionTracker();
-
   // Enables notifying to widget via NotifyOcclusionState() when the occlusion
   // state has been computed.
   void Enable(nsBaseWidget* aWindow, HWND aHwnd);
@@ -86,6 +81,7 @@ class WinWindowOcclusionTracker final
   friend class ::WinWindowOcclusionTrackerInteractiveTest;
 
   explicit WinWindowOcclusionTracker(base::Thread* aThread);
+  virtual ~WinWindowOcclusionTracker();
 
   // This class computes the occlusion state of the tracked windows.
   // It runs on a separate thread, and notifies the main thread of
@@ -245,8 +241,6 @@ class WinWindowOcclusionTracker final
     // Used to serialize tasks related to mRootWindowHwndsOcclusionState.
     RefPtr<SerializedTaskDispatcher> mSerializedTaskDispatcher;
 
-    ThreadSafeWeakPtr<WinWindowOcclusionTracker> mOcclusionTracker;
-
     friend class OcclusionUpdateRunnable;
   };