WebLayer MediaRouter: add services and notification IDs.

The services will be foregrounded and the notifications will be visible
when a cast session is ongoing. The service/notification ID design
matches that of MediaSession. The notification IDs are defined in client
xml, so //components/media_router code needs to ask the embedder for
these values.

Casting is still not functional in WebLayer even after this change as
a CastOptionsProvider is required.

Bug: 1057100
Change-Id: I4d6fa44d1073a0a26c618c501e58251f118379c1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2467197Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Auto-Submit: Evan Stade <estade@chromium.org>
Commit-Queue: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#817314}

chrome/android/java/res/values/ids.xml

@@ -26,6 +26,12 @@
     <!-- Media playback notification -->
     <item type="id" name="media_playback_notification" />
 
+    <!-- Remote Playback API notification -->
+    <item type="id" name="remote_playback_notification" />
+
+    <!-- Presentation API notification -->
+    <item type="id" name="presentation_notification" />
+
     <!-- Sync UI constants -->
     <item type="id" name="passphrase_type_list" />
 

chrome/android/java/src/org/chromium/chrome/browser/media/router/ChromeMediaRouterClient.java

@@ -12,6 +12,7 @@ import androidx.fragment.app.FragmentManager;
 import org.chromium.base.ApplicationStatus;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
+import org.chromium.chrome.R;
 import org.chromium.chrome.browser.document.ChromeIntentUtil;
 import org.chromium.chrome.browser.media.ui.ChromeMediaNotificationManager;
 import org.chromium.chrome.browser.tab.Tab;
@@ -41,6 +42,16 @@ public class ChromeMediaRouterClient extends MediaRouterClient {
         ChromeMediaNotificationManager.show(notificationInfo);
     }
 
+    @Override
+    public int getPresentationNotificationId() {
+        return R.id.presentation_notification;
+    }
+
+    @Override
+    public int getRemotingNotificationId() {
+        return R.id.remote_playback_notification;
+    }
+
     @Override
     public FragmentManager getSupportFragmentManager(WebContents initiator) {
         FragmentActivity currentActivity =

chrome/android/java/src/org/chromium/chrome/browser/media/ui/ChromeMediaNotificationControllerDelegate.java

@@ -187,7 +187,7 @@ class ChromeMediaNotificationControllerDelegate implements MediaNotificationCont
      * This class is used internally but has to be public to be able to launch the service.
      */
     public static final class CastListenerServiceImpl extends ListenerServiceImpl {
-        static final int NOTIFICATION_ID = R.id.remote_notification;
+        static final int NOTIFICATION_ID = R.id.remote_playback_notification;
 
         public CastListenerServiceImpl() {
             super(NOTIFICATION_ID);

components/media_router/browser/android/BUILD.gn

@@ -168,7 +168,6 @@ android_resources("java_resources") {
     "java/res/drawable/ic_cast_dark_chrome.xml",
     "java/res/layout/caf_controller_media_route_button.xml",
     "java/res/layout/expanded_cast_controller.xml",
-    "java/res/values/ids.xml",
     "java/res/values/styles.xml",
   ]
   deps = [

components/media_router/browser/android/java/res/values/ids.xml

-<?xml version="1.0" encoding="utf-8"?>
-
-<!-- Copyright 2020 The Chromium Authors. All rights reserved.
-
-     Use of this source code is governed by a BSD-style license that can be
-     found in the LICENSE file.
--->
-
-<resources>
-    <!-- RemotePlayback API notification -->
-    <item type="id" name="remote_notification" />
-
-    <!-- Presentation API notification -->
-    <item type="id" name="presentation_notification" />
-</resources>

components/media_router/browser/android/java/src/org/chromium/components/media_router/MediaRouterClient.java

@@ -49,6 +49,12 @@ public abstract class MediaRouterClient {
      */
     public abstract void showNotification(MediaNotificationInfo notificationInfo);
 
+    /** Returns the ID to be used for Presentation API notifications. */
+    public abstract int getPresentationNotificationId();
+
+    /** Returns the ID to be used for Remote Playback API notifications. */
+    public abstract int getRemotingNotificationId();
+
     /**
      * @param initiator the web contents that initiated the request.
      * @return a {@link FragmentManager} suitable for displaying a media router {@link

components/media_router/browser/android/java/src/org/chromium/components/media_router/TestMediaRouterClient.java

@@ -31,6 +31,16 @@ public class TestMediaRouterClient extends MediaRouterClient {
     @Override
     public void showNotification(MediaNotificationInfo notificationInfo) {}
 
+    @Override
+    public int getPresentationNotificationId() {
+        return 2;
+    }
+
+    @Override
+    public int getRemotingNotificationId() {
+        return 3;
+    }
+
     @Override
     public FragmentManager getSupportFragmentManager(WebContents initiator) {
         return null;

components/media_router/browser/android/java/src/org/chromium/components/media_router/caf/CafNotificationController.java

@@ -7,7 +7,7 @@ package org.chromium.components.media_router.caf;
 import android.content.Intent;
 
 import org.chromium.components.browser_ui.media.MediaNotificationUma;
-import org.chromium.components.media_router.R;
+import org.chromium.components.media_router.MediaRouterClient;
 
 /** NotificationController implementation for presentation. */
 public class CafNotificationController extends BaseNotificationController {
@@ -28,6 +28,6 @@ public class CafNotificationController extends BaseNotificationController {
 
     @Override
     public int getNotificationId() {
-        return R.id.presentation_notification;
+        return MediaRouterClient.getInstance().getPresentationNotificationId();
     }
 }

components/media_router/browser/android/java/src/org/chromium/components/media_router/caf/remoting/RemotingNotificationController.java

@@ -8,7 +8,7 @@ import android.content.Intent;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.components.browser_ui.media.MediaNotificationUma;
-import org.chromium.components.media_router.R;
+import org.chromium.components.media_router.MediaRouterClient;
 import org.chromium.components.media_router.caf.BaseNotificationController;
 import org.chromium.components.media_router.caf.BaseSessionController;
 
@@ -30,6 +30,6 @@ public class RemotingNotificationController extends BaseNotificationController {
 
     @Override
     public int getNotificationId() {
-        return R.id.remote_notification;
+        return MediaRouterClient.getInstance().getRemotingNotificationId();
     }
 }

weblayer/browser/content_browser_client_impl.cc

@@ -638,7 +638,7 @@ content::ControllerPresentationServiceDelegate*
 ContentBrowserClientImpl::GetControllerPresentationServiceDelegate(
     content::WebContents* web_contents) {
 #if defined(OS_ANDROID)
-  if (WebLayerFactoryImplAndroid::GetClientMajorVersion() < 87)
+  if (WebLayerFactoryImplAndroid::GetClientMajorVersion() < 88)
     return nullptr;
 
   if (base::FeatureList::IsEnabled(features::kMediaRouter)) {

weblayer/browser/java/BUILD.gn

@@ -150,6 +150,7 @@ android_library("java") {
     "org/chromium/weblayer_private/media/MediaRouteDialogFragmentImpl.java",
     "org/chromium/weblayer_private/media/MediaRouterClientImpl.java",
     "org/chromium/weblayer_private/media/MediaSessionManager.java",
+    "org/chromium/weblayer_private/media/MediaSessionNotificationHelper.java",
     "org/chromium/weblayer_private/media/MediaStreamManager.java",
     "org/chromium/weblayer_private/metrics/MetricsServiceClient.java",
     "org/chromium/weblayer_private/metrics/UmaUtils.java",
@@ -362,6 +363,7 @@ android_library("interfaces_java") {
     "org/chromium/weblayer_private/interfaces/NavigationState.java",
     "org/chromium/weblayer_private/interfaces/NewTabType.java",
     "org/chromium/weblayer_private/interfaces/ObjectWrapper.java",
+    "org/chromium/weblayer_private/interfaces/RemoteMediaServiceConstants.java",
     "org/chromium/weblayer_private/interfaces/ScrollNotificationType.java",
     "org/chromium/weblayer_private/interfaces/SettingType.java",
     "org/chromium/weblayer_private/interfaces/SiteSettingsFragmentArgs.java",

weblayer/browser/java/org/chromium/weblayer_private/WebLayerImpl.java

@@ -79,6 +79,7 @@ import org.chromium.weblayer_private.interfaces.IWebLayerClient;
 import org.chromium.weblayer_private.interfaces.ObjectWrapper;
 import org.chromium.weblayer_private.interfaces.StrictModeWorkaround;
 import org.chromium.weblayer_private.media.MediaRouteDialogFragmentImpl;
+import org.chromium.weblayer_private.media.MediaRouterClientImpl;
 import org.chromium.weblayer_private.media.MediaSessionManager;
 import org.chromium.weblayer_private.media.MediaStreamManager;
 import org.chromium.weblayer_private.metrics.MetricsServiceClient;
@@ -404,6 +405,19 @@ public final class WebLayerImpl extends IWebLayer.Stub {
         MediaSessionManager.serviceDestroyed();
     }
 
+    @Override
+    public void onRemoteMediaServiceStarted(IObjectWrapper sessionService, Intent intent) {
+        StrictModeWorkaround.apply();
+        MediaRouterClientImpl.serviceStarted(
+                ObjectWrapper.unwrap(sessionService, Service.class), intent);
+    }
+
+    @Override
+    public void onRemoteMediaServiceDestroyed(int id) {
+        StrictModeWorkaround.apply();
+        MediaRouterClientImpl.serviceDestroyed(id);
+    }
+
     @Override
     public IBinder initializeImageDecoder(IObjectWrapper appContext, IObjectWrapper remoteContext) {
         StrictModeWorkaround.apply();
@@ -513,6 +527,42 @@ public final class WebLayerImpl extends IWebLayer.Stub {
         }
     }
 
+    public static Intent createRemoteMediaServiceIntent() {
+        if (sClient == null) {
+            throw new IllegalStateException("WebLayer should have been initialized already.");
+        }
+
+        try {
+            return sClient.createRemoteMediaServiceIntent();
+        } catch (RemoteException e) {
+            throw new APICallException(e);
+        }
+    }
+
+    public static int getPresentationApiNotificationId() {
+        if (sClient == null) {
+            throw new IllegalStateException("WebLayer should have been initialized already.");
+        }
+
+        try {
+            return sClient.getPresentationApiNotificationId();
+        } catch (RemoteException e) {
+            throw new APICallException(e);
+        }
+    }
+
+    public static int getRemotePlaybackApiNotificationId() {
+        if (sClient == null) {
+            throw new IllegalStateException("WebLayer should have been initialized already.");
+        }
+
+        try {
+            return sClient.getRemotePlaybackApiNotificationId();
+        } catch (RemoteException e) {
+            throw new APICallException(e);
+        }
+    }
+
     public static String getClientApplicationName() {
         Context context = ContextUtils.getApplicationContext();
         return new StringBuilder()

weblayer/browser/java/org/chromium/weblayer_private/interfaces/IWebLayer.aidl

@@ -104,4 +104,8 @@ interface IWebLayer {
   IObjectWrapper getApplicationContext() = 20;
   IMediaRouteDialogFragment createMediaRouteDialogFragmentImpl(
       in IRemoteFragmentClient remoteFragmentClient) = 21;
+
+  // Added in Version 88.
+  void onRemoteMediaServiceStarted(in IObjectWrapper sessionService, in Intent intent) = 22;
+  void onRemoteMediaServiceDestroyed(int id) = 23;
 }

weblayer/browser/java/org/chromium/weblayer_private/interfaces/IWebLayerClient.aidl

@@ -18,4 +18,7 @@ interface IWebLayerClient {
   long getClassLoaderCreationTime() = 4;
   long getContextCreationTime() = 5;
   long getWebLayerLoaderCreationTime() = 6;
+  Intent createRemoteMediaServiceIntent() = 7;
+  int getPresentationApiNotificationId() = 8;
+  int getRemotePlaybackApiNotificationId() = 9;
 }

weblayer/browser/java/org/chromium/weblayer_private/interfaces/RemoteMediaServiceConstants.java

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.weblayer_private.interfaces;
+
+/** Keys for remote media service intent extras. */
+public interface RemoteMediaServiceConstants {
+    String NOTIFICATION_ID_KEY = "remote_media_service_notification_id_key";
+}

weblayer/browser/java/org/chromium/weblayer_private/media/MediaRouterClientImpl.java

@@ -4,23 +4,46 @@
 
 package org.chromium.weblayer_private.media;
 
+import android.app.Service;
 import android.content.Intent;
+import android.support.v4.media.session.MediaSessionCompat;
 
 import androidx.fragment.app.FragmentManager;
 
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
+import org.chromium.components.browser_ui.media.MediaNotificationController;
 import org.chromium.components.browser_ui.media.MediaNotificationInfo;
+import org.chromium.components.browser_ui.media.MediaNotificationManager;
+import org.chromium.components.browser_ui.notifications.NotificationWrapper;
+import org.chromium.components.browser_ui.notifications.NotificationWrapperBuilder;
 import org.chromium.components.media_router.MediaRouterClient;
 import org.chromium.content_public.browser.WebContents;
 import org.chromium.weblayer_private.IntentUtils;
 import org.chromium.weblayer_private.TabImpl;
+import org.chromium.weblayer_private.WebLayerImpl;
+import org.chromium.weblayer_private.interfaces.RemoteMediaServiceConstants;
 
 /** Provides WebLayer-specific behavior for Media Router. */
 @JNINamespace("weblayer")
 public class MediaRouterClientImpl extends MediaRouterClient {
+    static int sPresentationNotificationId;
+    static int sRemotingNotificationId;
+
     private MediaRouterClientImpl() {}
 
+    public static void serviceStarted(Service service, Intent intent) {
+        int notificationId = intent.getIntExtra(RemoteMediaServiceConstants.NOTIFICATION_ID_KEY, 0);
+        if (notificationId == 0) {
+            throw new RuntimeException("Invalid RemoteMediaService notification id");
+        }
+        MediaSessionNotificationHelper.serviceStarted(service, intent, notificationId);
+    }
+
+    public static void serviceDestroyed(int notificationId) {
+        MediaSessionNotificationHelper.serviceDestroyed(notificationId);
+    }
+
     @Override
     public int getTabId(WebContents webContents) {
         TabImpl tab = TabImpl.fromWebContents(webContents);
@@ -34,7 +57,19 @@ public class MediaRouterClientImpl extends MediaRouterClient {
 
     @Override
     public void showNotification(MediaNotificationInfo notificationInfo) {
-        // TODO: implement.
+        MediaNotificationManager.show(notificationInfo, () -> {
+            return new MediaRouterNotificationControllerDelegate(notificationInfo.id);
+        });
+    }
+
+    @Override
+    public int getPresentationNotificationId() {
+        return getPresentationNotificationIdFromClient();
+    }
+
+    @Override
+    public int getRemotingNotificationId() {
+        return getRemotingNotificationIdFromClient();
     }
 
     @Override
@@ -51,4 +86,62 @@ public class MediaRouterClientImpl extends MediaRouterClient {
 
         MediaRouterClient.setInstance(new MediaRouterClientImpl());
     }
+
+    private static class MediaRouterNotificationControllerDelegate
+            implements MediaNotificationController.Delegate {
+        // The ID distinguishes between Presentation and Remoting services/notifications.
+        private final int mNotificationId;
+
+        MediaRouterNotificationControllerDelegate(int notificationId) {
+            mNotificationId = notificationId;
+        }
+
+        @Override
+        public Intent createServiceIntent() {
+            return WebLayerImpl.createRemoteMediaServiceIntent().putExtra(
+                    RemoteMediaServiceConstants.NOTIFICATION_ID_KEY, mNotificationId);
+        }
+
+        @Override
+        public String getAppName() {
+            return WebLayerImpl.getClientApplicationName();
+        }
+
+        @Override
+        public String getNotificationGroupName() {
+            if (mNotificationId == getPresentationNotificationIdFromClient()) {
+                return "org.chromium.weblayer.PresentationApi";
+            }
+
+            assert mNotificationId == getRemotingNotificationIdFromClient();
+            return "org.chromium.weblayer.RemotePlaybackApi";
+        }
+
+        @Override
+        public NotificationWrapperBuilder createNotificationWrapperBuilder() {
+            return MediaSessionNotificationHelper.createNotificationWrapperBuilder(mNotificationId);
+        }
+
+        @Override
+        public void onMediaSessionUpdated(MediaSessionCompat session) {
+            // TODO(estade): implement.
+        }
+
+        @Override
+        public void logNotificationShown(NotificationWrapper notification) {}
+    }
+
+    private static int getPresentationNotificationIdFromClient() {
+        if (sPresentationNotificationId == 0) {
+            sPresentationNotificationId = WebLayerImpl.getPresentationApiNotificationId();
+        }
+        return sPresentationNotificationId;
+    }
+
+    private static int getRemotingNotificationIdFromClient() {
+        if (sRemotingNotificationId == 0) {
+            sRemotingNotificationId = WebLayerImpl.getRemotePlaybackApiNotificationId();
+        }
+        return sRemotingNotificationId;
+    }
 }

weblayer/browser/java/org/chromium/weblayer_private/media/MediaSessionManager.java

@@ -12,14 +12,10 @@ import org.chromium.components.browser_ui.media.MediaNotificationController;
 import org.chromium.components.browser_ui.media.MediaNotificationInfo;
 import org.chromium.components.browser_ui.media.MediaNotificationManager;
 import org.chromium.components.browser_ui.media.MediaSessionHelper;
-import org.chromium.components.browser_ui.notifications.ForegroundServiceUtils;
-import org.chromium.components.browser_ui.notifications.NotificationMetadata;
 import org.chromium.components.browser_ui.notifications.NotificationWrapper;
 import org.chromium.components.browser_ui.notifications.NotificationWrapperBuilder;
 import org.chromium.weblayer_private.IntentUtils;
 import org.chromium.weblayer_private.WebLayerImpl;
-import org.chromium.weblayer_private.WebLayerNotificationChannels;
-import org.chromium.weblayer_private.WebLayerNotificationWrapperBuilder;
 
 /**
  * A glue class for MediaSession.
@@ -31,24 +27,11 @@ public class MediaSessionManager {
     private static int sNotificationId;
 
     public static void serviceStarted(Service service, Intent intent) {
-        MediaNotificationController controller = getController();
-        if (controller != null && controller.processIntent(service, intent)) return;
-
-        // The service has been started with startForegroundService() but the
-        // notification hasn't been shown. See similar logic in {@link
-        // ChromeMediaNotificationControllerDelegate}.
-        MediaNotificationController.finishStartingForegroundServiceOnO(
-                service, createNotificationWrapperBuilder().buildNotificationWrapper());
-        // Call stopForeground to guarantee Android unset the foreground bit.
-        ForegroundServiceUtils.getInstance().stopForeground(
-                service, Service.STOP_FOREGROUND_REMOVE);
-        service.stopSelf();
+        MediaSessionNotificationHelper.serviceStarted(service, intent, getNotificationId());
     }
 
     public static void serviceDestroyed() {
-        MediaNotificationController controller = getController();
-        if (controller != null) controller.onServiceDestroyed();
-        MediaNotificationManager.clear(getNotificationId());
+        MediaSessionNotificationHelper.serviceDestroyed(getNotificationId());
     }
 
     public static MediaSessionHelper.Delegate createMediaSessionHelperDelegate(int tabId) {
@@ -60,7 +43,7 @@ public class MediaSessionManager {
 
             @Override
             public boolean fetchLargeFaviconImage() {
-                // TODO(crbug.com/1076463): WebLayer doesn't support favicons.
+                // TODO(crbug.com/1137625): implement.
                 return false;
             }
 
@@ -108,7 +91,8 @@ public class MediaSessionManager {
 
         @Override
         public NotificationWrapperBuilder createNotificationWrapperBuilder() {
-            return MediaSessionManager.createNotificationWrapperBuilder();
+            return MediaSessionNotificationHelper.createNotificationWrapperBuilder(
+                    getNotificationId());
         }
 
         @Override
@@ -120,22 +104,8 @@ public class MediaSessionManager {
         public void logNotificationShown(NotificationWrapper notification) {}
     }
 
-    private static NotificationWrapperBuilder createNotificationWrapperBuilder() {
-        // Only the null tag will work as expected, because {@link Service#startForeground()} only
-        // takes an ID and no tag. If we pass a tag here, then the notification that's used to
-        // display a paused state (no foreground service) will not be identified as the same one
-        // that's used with the foreground service.
-        return WebLayerNotificationWrapperBuilder.create(
-                WebLayerNotificationChannels.ChannelId.MEDIA_PLAYBACK,
-                new NotificationMetadata(0, null /*notificationTag*/, getNotificationId()));
-    }
-
     private static int getNotificationId() {
         if (sNotificationId == 0) sNotificationId = WebLayerImpl.getMediaSessionNotificationId();
         return sNotificationId;
     }
-
-    private static MediaNotificationController getController() {
-        return MediaNotificationManager.getController(getNotificationId());
-    }
 }

weblayer/browser/java/org/chromium/weblayer_private/media/MediaSessionNotificationHelper.java

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.weblayer_private.media;
+
+import android.app.Service;
+import android.content.Intent;
+
+import org.chromium.components.browser_ui.media.MediaNotificationController;
+import org.chromium.components.browser_ui.media.MediaNotificationManager;
+import org.chromium.components.browser_ui.notifications.ForegroundServiceUtils;
+import org.chromium.components.browser_ui.notifications.NotificationMetadata;
+import org.chromium.components.browser_ui.notifications.NotificationWrapperBuilder;
+import org.chromium.weblayer_private.WebLayerNotificationChannels;
+import org.chromium.weblayer_private.WebLayerNotificationWrapperBuilder;
+
+/**
+ * A helper class for management of MediaSession (local device), Presentation API and Remote
+ * Playback API (casting) notifications and foreground services.
+ */
+class MediaSessionNotificationHelper {
+    static void serviceStarted(Service service, Intent intent, int notificationId) {
+        MediaNotificationController controller =
+                MediaNotificationManager.getController(notificationId);
+        if (controller != null && controller.processIntent(service, intent)) return;
+
+        // The service has been started with startForegroundService() but the
+        // notification hasn't been shown. See similar logic in {@link
+        // ChromeMediaNotificationControllerDelegate}.
+        MediaNotificationController.finishStartingForegroundServiceOnO(service,
+                createNotificationWrapperBuilder(notificationId).buildNotificationWrapper());
+        // Call stopForeground to guarantee Android unset the foreground bit.
+        ForegroundServiceUtils.getInstance().stopForeground(
+                service, Service.STOP_FOREGROUND_REMOVE);
+        service.stopSelf();
+    }
+
+    static void serviceDestroyed(int notificationId) {
+        MediaNotificationController controller =
+                MediaNotificationManager.getController(notificationId);
+        if (controller != null) controller.onServiceDestroyed();
+        MediaNotificationManager.clear(notificationId);
+    }
+
+    static NotificationWrapperBuilder createNotificationWrapperBuilder(int notificationId) {
+        // Only the null tag will work as expected, because {@link Service#startForeground()} only
+        // takes an ID and no tag. If we pass a tag here, then the notification that's used to
+        // display a paused state (no foreground service) will not be identified as the same one
+        // that's used with the foreground service.
+        return WebLayerNotificationWrapperBuilder.create(
+                WebLayerNotificationChannels.ChannelId.MEDIA_PLAYBACK,
+                new NotificationMetadata(0, null /*notificationTag*/, notificationId));
+    }
+}

weblayer/public/java/AndroidManifest.xml

@@ -85,6 +85,13 @@
             </intent-filter>
         </service>
 
+        <service android:name="org.chromium.weblayer.RemoteMediaService"
+            android:exported="false">
+            <intent-filter>
+                <action android:name="android.intent.action.MEDIA_BUTTON" />
+            </intent-filter>
+        </service>
+
         <!-- Service for decoding images in a sandboxed process. -->
         <service
             android:name="org.chromium.weblayer.ImageDecoderService"

weblayer/public/java/BUILD.gn

@@ -70,6 +70,7 @@ android_library("java") {
     "org/chromium/weblayer/LoadError.java",
     "org/chromium/weblayer/MediaCaptureCallback.java",
     "org/chromium/weblayer/MediaCaptureController.java",
+    "org/chromium/weblayer/MediaPlaybackBaseService.java",
     "org/chromium/weblayer/MediaRouteDialogFragment.java",
     "org/chromium/weblayer/MediaSessionService.java",
     "org/chromium/weblayer/NavigateParams.java",
@@ -82,6 +83,7 @@ android_library("java") {
     "org/chromium/weblayer/ObserverList.java",
     "org/chromium/weblayer/Profile.java",
     "org/chromium/weblayer/RemoteFragment.java",
+    "org/chromium/weblayer/RemoteMediaService.java",
     "org/chromium/weblayer/ScrollNotificationType.java",
     "org/chromium/weblayer/ScrollOffsetCallback.java",
     "org/chromium/weblayer/SettingType.java",

weblayer/public/java/org/chromium/weblayer/MediaPlaybackBaseService.java

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.weblayer;
+
+import android.app.Service;
+import android.content.Intent;
+import android.os.IBinder;
+import android.os.RemoteException;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+/**
+ * Base class that provides common functionality for media playback services that are associated
+ * with an active media session and Android notification.
+ */
+abstract class MediaPlaybackBaseService extends Service {
+    // True when the start command has been forwarded to the impl.
+    boolean mStarted;
+
+    @Override
+    public IBinder onBind(Intent intent) {
+        return null;
+    }
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+
+        if (!WebLayer.hasWebLayerInitializationStarted()) {
+            stopSelf();
+            return;
+        }
+
+        init();
+    }
+
+    @Override
+    public int onStartCommand(Intent intent, int flags, int startId) {
+        WebLayer webLayer = getWebLayer();
+        if (webLayer == null) {
+            stopSelf();
+        } else {
+            try {
+                forwardStartCommandToImpl(webLayer, intent);
+            } catch (RemoteException e) {
+                throw new RuntimeException(e);
+            }
+            mStarted = true;
+        }
+
+        return START_NOT_STICKY;
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+
+        if (!mStarted) return;
+
+        try {
+            forwardDestroyToImpl();
+        } catch (RemoteException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    /** Called to do initialization when the service is created. */
+    void init() {}
+
+    /**
+     * Called to forward {@link onStartCommand()} to the WebLayer implementation.
+     *
+     * @param webLayer the implementation.
+     * @param intent the intent that started the service.
+     */
+    abstract void forwardStartCommandToImpl(@NonNull WebLayer webLayer, Intent intent)
+            throws RemoteException;
+
+    /**
+     * Called to forward {@link onDestroy()} to the WebLayer implementation.
+     *
+     * This will only be called if {@link forwardStartCommandToImpl()} was previously called, and
+     * there should always be a loaded {@link WebLayer} available via {@link getWebLayer()}.
+     */
+    abstract void forwardDestroyToImpl() throws RemoteException;
+
+    /** Returns the loaded {@link WebLayer}, or null if none is loaded. */
+    @Nullable
+    WebLayer getWebLayer() {
+        WebLayer webLayer;
+        try {
+            webLayer = WebLayer.getLoadedWebLayer(getApplication());
+        } catch (UnsupportedVersionException e) {
+            throw new RuntimeException(e);
+        }
+        return webLayer;
+    }
+}

weblayer/public/java/org/chromium/weblayer/MediaSessionService.java

@@ -9,9 +9,10 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.media.AudioManager;
-import android.os.IBinder;
 import android.os.RemoteException;
 
+import androidx.annotation.NonNull;
+
 import org.chromium.weblayer_private.interfaces.ObjectWrapper;
 
 /**
@@ -21,24 +22,20 @@ import org.chromium.weblayer_private.interfaces.ObjectWrapper;
  * foreground when the MediaSession is active.
  * @since 85
  */
-public class MediaSessionService extends Service {
+public class MediaSessionService extends MediaPlaybackBaseService {
     // A helper to automatically pause the media session when a user removes headphones.
     private BroadcastReceiver mAudioBecomingNoisyReceiver;
 
     @Override
-    public IBinder onBind(Intent intent) {
-        return null;
+    public void onDestroy() {
+        super.onDestroy();
+        if (mAudioBecomingNoisyReceiver != null) {
+            unregisterReceiver(mAudioBecomingNoisyReceiver);
+        }
     }
 
     @Override
-    public void onCreate() {
-        super.onCreate();
-
-        if (!WebLayer.hasWebLayerInitializationStarted()) {
-            stopSelf();
-            return;
-        }
-
+    void init() {
         mAudioBecomingNoisyReceiver = new BroadcastReceiver() {
             @Override
             public void onReceive(Context context, Intent intent) {
@@ -57,43 +54,13 @@ public class MediaSessionService extends Service {
     }
 
     @Override
-    public void onDestroy() {
-        super.onDestroy();
-
-        if (mAudioBecomingNoisyReceiver == null) return;
-
-        try {
-            getWebLayer().getImpl().onMediaSessionServiceDestroyed();
-        } catch (RemoteException e) {
-            throw new RuntimeException(e);
-        }
-
-        unregisterReceiver(mAudioBecomingNoisyReceiver);
+    void forwardStartCommandToImpl(@NonNull WebLayer webLayer, Intent intent)
+            throws RemoteException {
+        webLayer.getImpl().onMediaSessionServiceStarted(ObjectWrapper.wrap(this), intent);
     }
 
     @Override
-    public int onStartCommand(Intent intent, int flags, int startId) {
-        try {
-            WebLayer webLayer = getWebLayer();
-            if (webLayer == null) {
-                stopSelf();
-            } else {
-                webLayer.getImpl().onMediaSessionServiceStarted(ObjectWrapper.wrap(this), intent);
-            }
-        } catch (RemoteException e) {
-            throw new RuntimeException(e);
-        }
-
-        return START_NOT_STICKY;
-    }
-
-    private WebLayer getWebLayer() {
-        WebLayer webLayer;
-        try {
-            webLayer = WebLayer.getLoadedWebLayer(getApplication());
-        } catch (UnsupportedVersionException e) {
-            throw new RuntimeException(e);
-        }
-        return webLayer;
+    void forwardDestroyToImpl() throws RemoteException {
+        getWebLayer().getImpl().onMediaSessionServiceDestroyed();
     }
 }

weblayer/public/java/org/chromium/weblayer/RemoteMediaService.java

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.weblayer;
+
+import android.content.Intent;
+import android.os.RemoteException;
+
+import androidx.annotation.NonNull;
+
+import org.chromium.weblayer_private.interfaces.ObjectWrapper;
+import org.chromium.weblayer_private.interfaces.RemoteMediaServiceConstants;
+
+/**
+ * A foreground {@link Service} for Presentation API and Remote Playback API.
+ *
+ * Like {@link MediaSessionService}, this class is associated with a notification for an ongoing
+ * media session. The difference is that the media for this service is played back on a remote
+ * device, i.e. casting.
+ *
+ * @since 88
+ */
+public class RemoteMediaService extends MediaPlaybackBaseService {
+    private int mId;
+
+    @Override
+    void forwardStartCommandToImpl(@NonNull WebLayer webLayer, Intent intent)
+            throws RemoteException {
+        mId = intent.getIntExtra(RemoteMediaServiceConstants.NOTIFICATION_ID_KEY, 0);
+        if (mId == 0) throw new RuntimeException("Invalid RemoteMediaService notification id");
+
+        webLayer.getImpl().onRemoteMediaServiceStarted(ObjectWrapper.wrap(this), intent);
+    }
+
+    @Override
+    void forwardDestroyToImpl() throws RemoteException {
+        getWebLayer().getImpl().onRemoteMediaServiceDestroyed(mId);
+    }
+}

weblayer/public/java/org/chromium/weblayer/WebLayer.java

@@ -749,6 +749,26 @@ public class WebLayer {
         public long getWebLayerLoaderCreationTime() {
             return sWebLayerLoaderCreationTime;
         }
+
+        @Override
+        public Intent createRemoteMediaServiceIntent() {
+            StrictModeWorkaround.apply();
+            return new Intent(WebLayer.getAppContext(), RemoteMediaService.class);
+        }
+
+        @Override
+        public int getPresentationApiNotificationId() {
+            StrictModeWorkaround.apply();
+            // The id is part of the public library to avoid conflicts.
+            return R.id.weblayer_presentation_api_notification;
+        }
+
+        @Override
+        public int getRemotePlaybackApiNotificationId() {
+            StrictModeWorkaround.apply();
+            // The id is part of the public library to avoid conflicts.
+            return R.id.weblayer_remote_playback_api_notification;
+        }
     }
 
     @VerifiesOnO

weblayer/public/java/res/values/ids.xml

@@ -5,4 +5,6 @@
 
 <resources>
     <item type="id" name="weblayer_media_session_notification" />
+    <item type="id" name="weblayer_presentation_api_notification" />
+    <item type="id" name="weblayer_remote_playback_api_notification" />
 </resources>