Merge "Fix back to split pair from overview with shell-transition hang."

libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java

@@ -1207,6 +1207,27 @@ class StageCoordinator implements SplitLayout.SplitLayoutHandler,
         return out;
     }
 
+    @Override
+    public void onTransitionMerged(@NonNull IBinder transition) {
+        // Once the pending enter transition got merged, make sure to bring divider bar visible and
+        // clear the pending transition from cache to prevent mess-up the following state.
+        if (transition == mSplitTransitions.mPendingEnter) {
+            mSplitLayout.init();
+            setDividerVisibility(true, null /* transaction */);
+            setSplitsVisible(true);
+            mShouldUpdateRecents = true;
+            updateRecentTasksSplitPair();
+
+            if (!mLogger.hasStartedSession()) {
+                mLogger.logEnter(mSplitLayout.getDividerPositionAsFraction(),
+                        getMainStagePosition(), mMainStage.getTopChildTaskUid(),
+                        getSideStagePosition(), mSideStage.getTopChildTaskUid(),
+                        mSplitLayout.isLandscape());
+            }
+            mSplitTransitions.mPendingEnter = null;
+        }
+    }
+
     @Override
     public boolean startAnimation(@NonNull IBinder transition,
             @NonNull TransitionInfo info,

packages/SystemUI/shared/src/com/android/systemui/shared/system/RemoteTransitionCompat.java

@@ -246,10 +246,6 @@ public class RemoteTransitionCompat implements Parcelable {
                 if (mPausingTasks.contains(openingTasks.get(i).getContainer())) {
                     ++pauseMatches;
                 }
-                if (openingTasks.get(i).getContainer().equals(mPausingTasks.get(i))) {
-                    // In this case, we are "returning" to an already running app, so just consume
-                    // the merge and do nothing.
-                }
             }
             if (pauseMatches > 0) {
                 if (pauseMatches != mPausingTasks.size()) {
@@ -275,9 +271,9 @@ public class RemoteTransitionCompat implements Parcelable {
                 t.reparent(target.leash.mSurfaceControl, mInfo.getRootLeash());
                 t.setLayer(target.leash.mSurfaceControl, layer);
                 t.hide(target.leash.mSurfaceControl);
-                t.apply();
                 targets[i] = target;
             }
+            t.apply();
             recents.onTasksAppeared(targets);
             return true;
         }