Fix crash when overflow is selected and last bubble is removed

When the last bubble is removed we clean up the views associated with
the bubbles, including the overflow view.

BubbleOverflow#getExpandedView would create the view if it didn't exist
but it wouldn't be initialized which means it wouldn't have the Bubble
Positioner set on it.

When a bubble is removed some code runs that would do stuff to the
last expanded view, if it's non-null. If the overflow was the last bubble
expanded, rather than skipping that code because the expandedView is
null (because all the bubbles are gone), it was actually recreating
the overflow expandedView but it wouldn't be initialized at that time
resulting in the NPE.

This fixes the issue by modifying BubbleOverflow's getExpandedView to
only return the view, not do any view creation.

Additionally this change removes some redundant code in BubbleStackView.

Bug: 214399371
Test: atest BubbleOverflowTest
Change-Id: Ib8d94fc7ea1163e79146e1439ec3f404d3caa303

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

@@ -618,7 +618,8 @@ public class BubbleController {
     }
 
     /** Contains information to help position things on the screen. */
-    BubblePositioner getPositioner() {
+    @VisibleForTesting
+    public BubblePositioner getPositioner() {
         return mBubblePositioner;
     }
 

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

@@ -60,6 +60,7 @@ import android.widget.LinearLayout;
 
 import androidx.annotation.Nullable;
 
+import com.android.internal.annotations.VisibleForTesting;
 import com.android.internal.policy.ScreenDecorationsUtils;
 import com.android.wm.shell.R;
 import com.android.wm.shell.TaskView;
@@ -418,8 +419,9 @@ public class BubbleExpandedView extends LinearLayout {
         mPointerView.setBackground(mCurrentPointer);
     }
 
-    private String getBubbleKey() {
-        return mBubble != null ? mBubble.getKey() : "null";
+    @VisibleForTesting
+    public String getBubbleKey() {
+        return mBubble != null ? mBubble.getKey() : mIsOverflow ? BubbleOverflow.KEY : null;
     }
 
     /**

libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/BubbleOverflow.kt

@@ -54,6 +54,7 @@ class BubbleOverflow(
 
     /** Call before use and again if cleanUpExpandedState was called.  */
     fun initialize(controller: BubbleController) {
+        createExpandedView()
         getExpandedView()?.initialize(controller, controller.stackView, true /* isOverflow */)
     }
 
@@ -123,13 +124,15 @@ class BubbleOverflow(
         overflowBtn?.updateDotVisibility(true /* animate */)
     }
 
+    fun createExpandedView(): BubbleExpandedView? {
+        expandedView = inflater.inflate(R.layout.bubble_expanded_view,
+                null /* root */, false /* attachToRoot */) as BubbleExpandedView
+        expandedView?.applyThemeAttrs()
+        updateResources()
+        return expandedView
+    }
+
     override fun getExpandedView(): BubbleExpandedView? {
-        if (expandedView == null) {
-            expandedView = inflater.inflate(R.layout.bubble_expanded_view,
-                    null /* root */, false /* attachToRoot */) as BubbleExpandedView
-            expandedView?.applyThemeAttrs()
-            updateResources()
-        }
         return expandedView
     }
 

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

@@ -787,7 +787,7 @@ public class BubbleStackView extends FrameLayout
         ta.recycle();
 
         final Runnable onBubbleAnimatedOut = () -> {
-            if (getBubbleCount() == 0 && !mBubbleData.isShowingOverflow()) {
+            if (getBubbleCount() == 0) {
                 mBubbleController.onAllBubblesAnimatedOut();
             }
         };
@@ -1651,7 +1651,6 @@ public class BubbleStackView extends FrameLayout
                 } else {
                     bubble.cleanupViews();
                 }
-                updatePointerPosition(false /* forIme */);
                 updateExpandedView();
                 logBubbleEvent(bubble, FrameworkStatsLog.BUBBLE_UICHANGED__ACTION__DISMISSED);
                 return;

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/BubbleOverflowTest.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.wm.shell;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import android.testing.AndroidTestingRunner;
+import android.testing.TestableLooper;
+import android.view.WindowManager;
+
+import androidx.test.filters.SmallTest;
+
+import com.android.wm.shell.bubbles.BubbleController;
+import com.android.wm.shell.bubbles.BubbleOverflow;
+import com.android.wm.shell.bubbles.BubbleStackView;
+import com.android.wm.shell.bubbles.TestableBubblePositioner;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+
+/**
+ * Unit tests for {@link com.android.wm.shell.bubbles.BubbleOverflow}.
+ */
+@SmallTest
+@RunWith(AndroidTestingRunner.class)
+@TestableLooper.RunWithLooper(setAsMainLooper = true)
+public class BubbleOverflowTest extends ShellTestCase {
+
+    private TestableBubblePositioner mPositioner;
+    private BubbleOverflow mOverflow;
+
+    @Mock
+    private BubbleController mBubbleController;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+
+        mPositioner = new TestableBubblePositioner(mContext, mock(WindowManager.class));
+        when(mBubbleController.getPositioner()).thenReturn(mPositioner);
+        when(mBubbleController.getStackView()).thenReturn(mock(BubbleStackView.class));
+
+        mOverflow = new BubbleOverflow(mContext, mPositioner);
+    }
+
+    @Test
+    public void test_initialize() {
+        assertThat(mOverflow.getExpandedView()).isNull();
+
+        mOverflow.initialize(mBubbleController);
+
+        assertThat(mOverflow.getExpandedView()).isNotNull();
+        assertThat(mOverflow.getExpandedView().getBubbleKey()).isEqualTo(BubbleOverflow.KEY);
+    }
+
+    @Test
+    public void test_cleanUpExpandedState() {
+        mOverflow.createExpandedView();
+        assertThat(mOverflow.getExpandedView()).isNotNull();
+
+        mOverflow.cleanUpExpandedState();
+        assertThat(mOverflow.getExpandedView()).isNull();
+    }
+
+}