Add logging for bubble flyout action.

Bug: 123543171
Test: manual
Change-Id: I7b0a21c0a0c23c211e4c72ec5b2dfc7ea60537d6

cmds/statsd/src/atoms.proto

@@ -5575,6 +5575,7 @@ message BubbleUIChanged {
         SWIPE_LEFT = 13;
         SWIPE_RIGHT = 14;
         STACK_EXPANDED = 15;
+        FLYOUT = 16;
     }
     optional Action action = 6;
 

packages/SystemUI/src/com/android/systemui/bubbles/BubbleStackView.java

@@ -889,6 +889,7 @@ public class BubbleStackView extends FrameLayout {
                 mFlyout.removeCallbacks(mHideFlyout);
                 mFlyout.postDelayed(mHideFlyout, FLYOUT_HIDE_AFTER);
             });
+            logBubbleEvent(bubble, StatsLog.BUBBLE_UICHANGED__ACTION__FLYOUT);
         }
     }
 
@@ -1060,7 +1061,8 @@ public class BubbleStackView extends FrameLayout {
      * @param action the user interaction enum.
      */
     private void logBubbleEvent(@Nullable Bubble bubble, int action) {
-        if (bubble == null) {
+        if (bubble == null || bubble.entry == null
+                || bubble.entry.notification == null) {
             StatsLog.write(StatsLog.BUBBLE_UI_CHANGED,
                     null /* package name */,
                     null /* notification channel */,