Disable pooling of MessagingGroup and MessagingMessage instances.

A bug with the pooling may be causing a content crossover between notifications that (despite being purely visual) is extremely unnerving for users.

Bug: 208508846
Test: manual
Change-Id: Iabfd62ba4ecc776805eae0c5e6e807856c682441

core/java/com/android/internal/widget/MessagingGroup.java

@@ -32,7 +32,6 @@ import android.graphics.drawable.Icon;
 import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.util.DisplayMetrics;
-import android.util.Pools;
 import android.util.TypedValue;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -57,8 +56,8 @@ import java.util.List;
  */
 @RemoteViews.RemoteView
 public class MessagingGroup extends LinearLayout implements MessagingLinearLayout.MessagingChild {
-    private static Pools.SimplePool<MessagingGroup> sInstancePool
-            = new Pools.SynchronizedPool<>(10);
+    private static final MessagingPool<MessagingGroup> sInstancePool =
+            new MessagingPool<>(10);
 
     /**
      * Images are displayed inline.
@@ -338,7 +337,7 @@ public class MessagingGroup extends LinearLayout implements MessagingLinearLayou
     }
 
     public static void dropCache() {
-        sInstancePool = new Pools.SynchronizedPool<>(10);
+        sInstancePool.clear();
     }
 
     @Override

core/java/com/android/internal/widget/MessagingImageMessage.java

@@ -28,7 +28,6 @@ import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.util.AttributeSet;
 import android.util.Log;
-import android.util.Pools;
 import android.view.LayoutInflater;
 import android.view.ViewGroup;
 import android.widget.ImageView;
@@ -44,8 +43,8 @@ import java.io.IOException;
 @RemoteViews.RemoteView
 public class MessagingImageMessage extends ImageView implements MessagingMessage {
     private static final String TAG = "MessagingImageMessage";
-    private static Pools.SimplePool<MessagingImageMessage> sInstancePool
-            = new Pools.SynchronizedPool<>(10);
+    private static final MessagingPool<MessagingImageMessage> sInstancePool =
+            new MessagingPool<>(10);
     private final MessagingMessageState mState = new MessagingMessageState(this);
     private final int mMinImageHeight;
     private final Path mPath = new Path();
@@ -194,7 +193,7 @@ public class MessagingImageMessage extends ImageView implements MessagingMessage
     }
 
     public static void dropCache() {
-        sInstancePool = new Pools.SynchronizedPool<>(10);
+        sInstancePool.clear();
     }
 
     @Override

core/java/com/android/internal/widget/MessagingPool.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2021 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.internal.widget;
+
+import android.util.Pools;
+
+/**
+ * A trivial wrapper around Pools.SynchronizedPool which allows clearing the pool, as well as
+ * disabling the pool class altogether.
+ * @param <T> the type of object in the pool
+ */
+public class MessagingPool<T> implements Pools.Pool<T> {
+    private static final boolean ENABLED = false;  // disabled to test b/208508846
+    private final int mMaxPoolSize;
+    private Pools.SynchronizedPool<T> mCurrentPool;
+
+    public MessagingPool(int maxPoolSize) {
+        mMaxPoolSize = maxPoolSize;
+        if (ENABLED) {
+            mCurrentPool = new Pools.SynchronizedPool<>(mMaxPoolSize);
+        }
+    }
+
+    @Override
+    public T acquire() {
+        return ENABLED ? mCurrentPool.acquire() : null;
+    }
+
+    @Override
+    public boolean release(T instance) {
+        return ENABLED && mCurrentPool.release(instance);
+    }
+
+    /** Clear the pool */
+    public void clear() {
+        if (ENABLED) {
+            mCurrentPool = new Pools.SynchronizedPool<>(mMaxPoolSize);
+        }
+    }
+
+}

core/java/com/android/internal/widget/MessagingTextMessage.java

@@ -24,7 +24,6 @@ import android.app.Notification;
 import android.content.Context;
 import android.text.Layout;
 import android.util.AttributeSet;
-import android.util.Pools;
 import android.view.LayoutInflater;
 import android.widget.RemoteViews;
 
@@ -36,8 +35,8 @@ import com.android.internal.R;
 @RemoteViews.RemoteView
 public class MessagingTextMessage extends ImageFloatingTextView implements MessagingMessage {
 
-    private static Pools.SimplePool<MessagingTextMessage> sInstancePool
-            = new Pools.SynchronizedPool<>(20);
+    private static final MessagingPool<MessagingTextMessage> sInstancePool =
+            new MessagingPool<>(20);
     private final MessagingMessageState mState = new MessagingMessageState(this);
 
     public MessagingTextMessage(@NonNull Context context) {
@@ -92,7 +91,7 @@ public class MessagingTextMessage extends ImageFloatingTextView implements Messa
     }
 
     public static void dropCache() {
-        sInstancePool = new Pools.SynchronizedPool<>(10);
+        sInstancePool.clear();
     }
 
     @Override