Stash the taskbar on every bubble bar expansion

Added logic to enable BubbleBarView to  notify BubbleBarViewController
of expanded state change. Also updated all the test that uses
BubbleBarView to pass empty Controller.

Fixes: 411304392
Flag: com.android.wm.shell.enable_bubble_bar
Test: Manual. Go to any app. Swipe up to show the taskbar. Trigger any
bubble. Observe taskbar is stashed on bubble bar expanded.

Change-Id: I88ad167eb0ed444629716df3672bbb06ca8adcc4

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

@@ -318,6 +318,14 @@ public class BubbleBarViewController {
             public void setIsDragging(boolean dragging) {
                 mBubbleBarContainer.setElevation(dragging ? mDragElevation : 0);
             }
+
+            @Override
+            public void onBubbleBarExpandedStateChanged(boolean expanded) {
+                if (expanded && !mTaskbarStashController.isStashed()) {
+                    mTaskbarStashController.updateAndAnimateTransientTaskbar(true /* stash */,
+                            false /* shouldBubblesFollow */);
+                }
+            }
         });
 
         mBubbleViewController = new BubbleView.Controller() {
@@ -1252,8 +1260,6 @@ public class BubbleBarViewController {
                 mSystemUiProxy.collapseBubbles();
             } else {
                 mBubbleBarController.showSelectedBubble();
-                mTaskbarStashController.updateAndAnimateTransientTaskbar(true /* stash */,
-                        false /* shouldBubblesFollow */);
             }
         }
     }