Merge "Fix split screen divider corners flicker" into tm-dev am: 0610af43d3

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/17005477

Change-Id: Id42c1ce139e4cd36226972eea08e746b83e18fcb

quickstep/src/com/android/quickstep/AbsSwipeUpHandler.java

@@ -833,12 +833,9 @@ public abstract class AbsSwipeUpHandler<T extends StatefulActivity<S>,
         // Notify when the animation starts
         flushOnRecentsAnimationAndLauncherBound();
 
-        // Start hiding the divider
-        setDividerShown(false /* shown */, false /* immediate */);
-
         // Only add the callback to enable the input consumer after we actually have the controller
         mStateCallback.runOnceAtState(STATE_APP_CONTROLLER_RECEIVED | STATE_GESTURE_STARTED,
-                mRecentsAnimationController::enableInputConsumer);
+                this::startInterceptingTouchesForGesture);
         mStateCallback.setStateOnUiThread(STATE_APP_CONTROLLER_RECEIVED);
 
         mPassedOverviewThreshold = false;
@@ -1457,6 +1454,17 @@ public abstract class AbsSwipeUpHandler<T extends StatefulActivity<S>,
         return swipePipToHomeAnimator;
     }
 
+    private void startInterceptingTouchesForGesture() {
+        if (mRecentsAnimationController == null) {
+            return;
+        }
+
+        mRecentsAnimationController.enableInputConsumer();
+
+        // Start hiding the divider
+        setDividerShown(false /* shown */, true /* immediate */);
+    }
+
     private void computeRecentsScrollIfInvisible() {
         if (mRecentsView != null && mRecentsView.getVisibility() != View.VISIBLE) {
             // Views typically don't compute scroll when invisible as an optimization,