Merge cherrypicks of [16778403] into sc-v2-release.

Change-Id: Ie5649ce77ccb6510d5677112b84c09e1e6429324

libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/BubbleStackView.java

@@ -1724,6 +1724,7 @@ public class BubbleStackView extends FrameLayout
 
     /**
      * Changes the expanded state of the stack.
+     * Don't call this directly, call mBubbleData#setExpanded.
      *
      * @param shouldExpand whether the bubble stack should appear expanded
      */
@@ -1770,7 +1771,7 @@ public class BubbleStackView extends FrameLayout
             } else if (mManageEduView != null && mManageEduView.getVisibility() == VISIBLE) {
                 mManageEduView.hide();
             } else {
-                setExpanded(false);
+                mBubbleData.setExpanded(false);
             }
         }
     }

packages/SystemUI/tests/src/com/android/systemui/wmshell/BubblesTest.java

@@ -1275,6 +1275,22 @@ public class BubblesTest extends SysuiTestCase {
         assertSysuiStates(false /* stackExpanded */, false /* mangeMenuExpanded */);
     }
 
+    @Test
+    public void testStackViewOnBackPressed_updatesBubbleDataExpandState() {
+        mBubbleController.updateBubble(mBubbleEntry);
+
+        // Expand the stack
+        mBubbleData.setExpanded(true);
+        assertStackExpanded();
+
+        // Hit back
+        BubbleStackView stackView = mBubbleController.getStackView();
+        stackView.onBackPressed();
+
+        // Make sure we're collapsed
+        assertStackCollapsed();
+    }
+
     /** Creates a bubble using the userId and package. */
     private Bubble createBubble(int userId, String pkg) {
         final UserHandle userHandle = new UserHandle(userId);

packages/SystemUI/tests/src/com/android/systemui/wmshell/NewNotifPipelineBubblesTest.java

@@ -1091,6 +1091,22 @@ public class NewNotifPipelineBubblesTest extends SysuiTestCase {
         assertSysuiStates(false /* stackExpanded */, false /* mangeMenuExpanded */);
     }
 
+    @Test
+    public void testStackViewOnBackPressed_updatesBubbleDataExpandState() {
+        mBubbleController.updateBubble(mBubbleEntry);
+
+        // Expand the stack
+        mBubbleData.setExpanded(true);
+        assertStackExpanded();
+
+        // Hit back
+        BubbleStackView stackView = mBubbleController.getStackView();
+        stackView.onBackPressed();
+
+        // Make sure we're collapsed
+        assertStackCollapsed();
+    }
+
     /**
      * Sets the bubble metadata flags for this entry. These flags are normally set by
      * NotificationManagerService when the notification is sent, however, these tests do not