Fix leakage of DisplayContent referenced from TransitionController

Unlike AppTransition which is associated DisplayContent, the
TransitionController is a global instance. So it needs to unregister
the listener when the display is removed.

Bug: 214991741
Test: Start/stop screen recording multiple times (create virtual
      display). The heap dump of system server should not contain
      many DisplayContent instances.
(cherry picked from commit 491914c17c869a174f91d0414181d1be11e040a3)
(cherry picked from commit c3eaf662257919343210b96f5d5aef161df0723e)
Merged-In: I44e2a794981fc114ada0ce98cd2471adf623d856
Change-Id: I44e2a794981fc114ada0ce98cd2471adf623d856

4 files changed, 6 insertions, 2 deletions

diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 40549548da62..1e31fdab30d0 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -1067,8 +1067,6 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
 
         mAppTransition = new AppTransition(mWmService.mContext, mWmService, this);
         mAppTransition.registerListenerLocked(mWmService.mActivityManagerAppTransitionNotifier);
-        mTransitionController.registerLegacyListener(
-                mWmService.mActivityManagerAppTransitionNotifier);
         mAppTransition.registerListenerLocked(mFixedRotationTransitionListener);
         mAppTransitionController = new AppTransitionController(mWmService, this);
         mUnknownAppVisibilityController = new UnknownAppVisibilityController(mWmService, this);
diff --git a/services/core/java/com/android/server/wm/DisplayPolicy.java b/services/core/java/com/android/server/wm/DisplayPolicy.java
index ef3c5a3df84e..1ff2ebeb8c14 100644
--- a/services/core/java/com/android/server/wm/DisplayPolicy.java
+++ b/services/core/java/com/android/server/wm/DisplayPolicy.java
@@ -3311,6 +3311,7 @@ public class DisplayPolicy {
     }
 
     void release() {
+        mDisplayContent.mTransitionController.unregisterLegacyListener(mAppTransitionListener);
         mHandler.post(mGestureNavigationSettingsObserver::unregister);
     }
 
diff --git a/services/core/java/com/android/server/wm/TransitionController.java b/services/core/java/com/android/server/wm/TransitionController.java
index e05457010df8..929ec3b929b2 100644
--- a/services/core/java/com/android/server/wm/TransitionController.java
+++ b/services/core/java/com/android/server/wm/TransitionController.java
@@ -430,6 +430,10 @@ class TransitionController {
         mLegacyListeners.add(listener);
     }
 
+    void unregisterLegacyListener(WindowManagerInternal.AppTransitionListener listener) {
+        mLegacyListeners.remove(listener);
+    }
+
     void dispatchLegacyAppTransitionPending() {
         for (int i = 0; i < mLegacyListeners.size(); ++i) {
             mLegacyListeners.get(i).onAppTransitionPendingLocked();
diff --git a/services/core/java/com/android/server/wm/WindowOrganizerController.java b/services/core/java/com/android/server/wm/WindowOrganizerController.java
index 42766bdb0732..6970c7942a50 100644
--- a/services/core/java/com/android/server/wm/WindowOrganizerController.java
+++ b/services/core/java/com/android/server/wm/WindowOrganizerController.java
@@ -137,6 +137,7 @@ class WindowOrganizerController extends IWindowOrganizerController.Stub
 
     void setWindowManager(WindowManagerService wms) {
         mTransitionController = new TransitionController(mService, wms.mTaskSnapshotController);
+        mTransitionController.registerLegacyListener(wms.mActivityManagerAppTransitionNotifier);
     }
 
     TransitionController getTransitionController() {