Don't reset alpha after dragging to dismiss

After dragging the bubble bar to dismiss, don't reset its alpha
value.

Flag: com.android.wm.shell.enable_bubble_bar
Fixes: 359804931
Test: manual
      - Create a bubble in the bubble bar
      - Drag bubble bar to dismiss
      - Create another bubble
      - Observe the new bubble does not flicker
Change-Id: I8d56f71d38ec33acda8efade50735b59254d77d4

quickstep/src/com/android/launcher3/taskbar/bubbles/BubbleBarView.java

@@ -647,7 +647,9 @@ public class BubbleBarView extends FrameLayout {
         }
         setAlphaDuringBubbleDrag(1f);
         setTranslationX(0f);
-        setAlpha(1f);
+        if (getBubbleChildCount() > 0) {
+            setAlpha(1f);
+        }
     }
 
     /**

quickstep/src/com/android/launcher3/taskbar/bubbles/BubbleDragAnimator.java

@@ -128,7 +128,7 @@ public class BubbleDragAnimator {
                         boolean wasFling, boolean canceled, float finalValue, float finalVelocity,
                         boolean allRelevantPropertyAnimationsEnded) -> {
                     if (canceled || allRelevantPropertyAnimationsEnded) {
-                        resetAnimatedViews(restingPosition);
+                        resetAnimatedViews(restingPosition, /* dismissed= */ false);
                         if (endActions != null) {
                             endActions.run();
                         }
@@ -197,7 +197,7 @@ public class BubbleDragAnimator {
                         boolean wasFling, boolean canceled, float finalValue, float finalVelocity,
                         boolean allRelevantPropertyAnimationsEnded) -> {
                     if (canceled || allRelevantPropertyAnimationsEnded) {
-                        resetAnimatedViews(initialPosition);
+                        resetAnimatedViews(initialPosition, /* dismissed= */ true);
                         if (endActions != null) endActions.run();
                     }
                 })
@@ -208,11 +208,14 @@ public class BubbleDragAnimator {
      * Reset the animated views to the initial state
      *
      * @param initialPosition position of the bubble
+     * @param dismissed whether the animated view was dismissed
      */
-    private void resetAnimatedViews(@NonNull PointF initialPosition) {
+    private void resetAnimatedViews(@NonNull PointF initialPosition, boolean dismissed) {
         mView.setScaleX(1f);
         mView.setScaleY(1f);
-        mView.setAlpha(1f);
+        if (!dismissed) {
+            mView.setAlpha(1f);
+        }
         mView.setTranslationX(initialPosition.x);
         mView.setTranslationY(initialPosition.y);