[Chromecast] Do not recreate intent receiver in start

CastWebContentsComponent.start() is called everytime when saying "OKG,
play next" before the media app is stopped by a voice command. Because
we lose the reference to the old intent receiver, the
old one has no chance to unregister from LocalBroadcastManager, which
would cause memory leak.

Change-Id: Ie16fb82c220c48c5410cf57a6d829b2984880d95
Bug: b/73789608
Test: cast_shell_junit_tests
Reviewed-on: https://chromium-review.googlesource.com/933581Reviewed-by: Luke Halliwell <halliwell@chromium.org>
Commit-Queue: Zhiheng(Vincent) Li <vincentli@google.com>
Cr-Commit-Position: refs/heads/master@{#539904}

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsComponent.java

@@ -17,6 +17,7 @@ import android.support.v4.content.LocalBroadcastManager;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
+import org.chromium.base.VisibleForTesting;
 import org.chromium.content_public.browser.WebContents;
 
 /**
@@ -38,7 +39,8 @@ public class CastWebContentsComponent {
      */
     public interface OnKeyDownHandler { void onKeyDown(int keyCode); }
 
-    private interface Delegate {
+    @VisibleForTesting
+    interface Delegate {
         void start(Context context, WebContents webContents);
         void stop(Context context);
     }
@@ -181,12 +183,11 @@ public class CastWebContentsComponent {
     private static final String ACTION_ACTIVITY_STOPPED =
             "com.google.android.apps.castshell.intent.action.ACTIVITY_STOPPED";
 
-    private final Delegate mDelegate;
     private final OnComponentClosedHandler mComponentClosedHandler;
     private final OnKeyDownHandler mKeyDownHandler;
+    private final String mInstanceId;
+    private Delegate mDelegate;
     private Receiver mReceiver;
-    private String mInstanceId;
-    private boolean mStarted = false;
 
     public CastWebContentsComponent(String instanceId,
             OnComponentClosedHandler onComponentClosedHandler, OnKeyDownHandler onKeyDownHandler,
@@ -194,6 +195,11 @@ public class CastWebContentsComponent {
         mComponentClosedHandler = onComponentClosedHandler;
         mKeyDownHandler = onKeyDownHandler;
         mInstanceId = instanceId;
+        if (DEBUG) {
+            Log.d(TAG,
+                    "New CastWebContentsComponent. Instance ID: " + instanceId + "; isHeadless: "
+                            + isHeadless + "; enableTouchInput:" + enableTouchInput);
+        }
         if (BuildConfig.DISPLAY_WEB_CONTENTS_IN_SERVICE || isHeadless) {
             if (DEBUG) Log.d(TAG, "Creating service delegate...");
             mDelegate = new ServiceDelegate();
@@ -207,31 +213,52 @@ public class CastWebContentsComponent {
     }
 
     public void start(Context context, WebContents webContents) {
-        if (DEBUG) Log.d(TAG, "start with delegate: " + mDelegate.getClass().getSimpleName());
+        if (DEBUG) {
+            Log.d(TAG,
+                    "start with delegate: " + mDelegate.getClass().getSimpleName()
+                            + "; Instance ID: " + mInstanceId);
+        }
 
         Uri instanceUri = getInstanceUri(mInstanceId);
-        mReceiver = new Receiver();
-        IntentFilter filter = new IntentFilter();
-        filter.addAction(ACTION_ACTIVITY_STOPPED);
-        filter.addAction(ACTION_KEY_EVENT);
-        filter.addDataScheme(instanceUri.getScheme());
-        filter.addDataAuthority(instanceUri.getAuthority(), null);
-        filter.addDataPath(instanceUri.getPath(), PatternMatcher.PATTERN_LITERAL);
-
-        if (DEBUG) Log.d(TAG, "Registering mReceiver");
-        getLocalBroadcastManager().registerReceiver(mReceiver, filter);
-
-        mDelegate.start(context, webContents);
-        mStarted = true;
+        if (mReceiver == null) {
+            mReceiver = new Receiver();
+            IntentFilter filter = new IntentFilter();
+            filter.addAction(ACTION_ACTIVITY_STOPPED);
+            filter.addAction(ACTION_KEY_EVENT);
+            filter.addDataScheme(instanceUri.getScheme());
+            filter.addDataAuthority(instanceUri.getAuthority(), null);
+            filter.addDataPath(instanceUri.getPath(), PatternMatcher.PATTERN_LITERAL);
+
+            if (DEBUG) Log.d(TAG, "Registering mReceiver");
+            getLocalBroadcastManager().registerReceiver(mReceiver, filter);
+
+            mDelegate.start(context, webContents);
+        } else {
+            if (DEBUG) Log.d(TAG, "Receiver already created.");
+        }
+    }
+
+    @VisibleForTesting
+    Receiver getIntentReceiver() {
+        return mReceiver;
+    }
+
+    @VisibleForTesting
+    void setDelegate(Delegate delegate) {
+        mDelegate = delegate;
     }
 
     public void stop(Context context) {
-        if (DEBUG) Log.d(TAG, "stop");
-        if (mStarted) {
+        if (DEBUG) {
+            Log.d(TAG,
+                    "stop with delegate: " + mDelegate.getClass().getSimpleName()
+                            + "; Instance ID: " + mInstanceId);
+        }
+        if (mReceiver != null) {
             getLocalBroadcastManager().unregisterReceiver(mReceiver);
             if (DEBUG) Log.d(TAG, "Call delegate to stop");
             mDelegate.stop(context);
-            mStarted = false;
+            mReceiver = null;
         }
     }
 

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsSurfaceHelper.java

@@ -95,8 +95,8 @@ class CastWebContentsSurfaceHelper {
             IntentFilter filter = new IntentFilter();
             filter.addAction(CastIntents.ACTION_STOP_WEB_CONTENT);
             return new LocalBroadcastReceiverScope(filter, (Intent intent) -> {
-                Log.d(TAG, "Intent action=" + intent.getAction());
                 String intentUri = intent.getStringExtra(CastWebContentsComponent.INTENT_EXTRA_URI);
+                Log.d(TAG, "Intent action=" + intent.getAction() + "; URI=" + intentUri);
                 if (!uri.toString().equals(intentUri)) {
                     Log.d(TAG, "Current URI=" + uri + "; intent URI=" + intentUri);
                     return;
@@ -140,14 +140,15 @@ class CastWebContentsSurfaceHelper {
             @Override
             public void run() {
                 if (currentInstanceId != null && currentInstanceId.equals(mInstanceId)) {
-                    Log.d(TAG, "Finishing.");
                     if (mShowInFragment) {
                         Intent in = new Intent();
                         in.setAction(CastIntents.ACTION_ON_WEB_CONTENT_STOPPED);
                         in.putExtra(CastWebContentsComponent.INTENT_EXTRA_URI, mUri.toString());
+                        Log.d(TAG, "Sending intent: ON_WEB_CONTENT_STOPPED: URI=" + mUri);
                         LocalBroadcastManager.getInstance(ContextUtils.getApplicationContext())
                                 .sendBroadcastSync(in);
                     } else {
+                        Log.d(TAG, "Finishing cast content activity of URI:" + mUri);
                         mHostActivity.finish();
                     }
                 }

chromecast/browser/android/junit/src/org/chromium/chromecast/shell/CastWebContentsComponentTest.java

@@ -6,7 +6,9 @@ package org.chromium.chromecast.shell;
 
 import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.eq;
+import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 
 import android.app.Activity;
@@ -165,4 +167,23 @@ public class CastWebContentsComponentTest {
 
         verify(mActivity, never()).unbindService(any(ServiceConnection.class));
     }
+
+    @Test
+    public void testStartWebContentsComponentMultipleTimes() {
+        CastWebContentsComponent component =
+                new CastWebContentsComponent(INSTANCE_ID, null, null, false, false);
+        CastWebContentsComponent.Delegate delegate = mock(CastWebContentsComponent.Delegate.class);
+        component.setDelegate(delegate);
+        component.start(mActivity, mWebContents);
+        Object receiver1 = component.getIntentReceiver();
+        Assert.assertNotNull(receiver1);
+        verify(delegate, times(1)).start(eq(mActivity), eq(mWebContents));
+        component.start(mActivity, mWebContents);
+        Object receiver2 = component.getIntentReceiver();
+        Assert.assertEquals(receiver1, receiver2);
+        verify(delegate, times(1)).start(any(Context.class), any(WebContents.class));
+        component.stop(mActivity);
+        Assert.assertNull(component.getIntentReceiver());
+        verify(delegate, times(1)).stop(any(Context.class));
+    }
 }