Implement GCMDriver.java using MultiplexingGcmListener

Known caveat:
- Since GCM on Android only supports a single registration per native
  app, only a single web app can register at once, and even then only
  if they pass --disable-sync-gcm-in-order-to-try-push-api on the command
  line which disables Chrome Sync etc from receiving GCM messages.

Depends on https://codereview.chromium.org/316963003/

BUG=350384

Review URL: https://codereview.chromium.org/314293006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@276795 0039d316-1c4b-4281-b951-d872f2087c98

chrome/android/shell/java/AndroidManifest.xml

@@ -168,6 +168,16 @@
             </intent-filter>
         </receiver>
 
+        <!-- GCMDriver multiplexed GCM receiver -->
+        <service android:exported="false"
+                 android:name="org.chromium.components.gcm_driver.GCMListener"/>
+        <receiver android:exported="false"
+                  android:name="org.chromium.components.gcm_driver.GCMListener$Receiver">
+            <intent-filter>
+                <action android:name="com.google.ipc.invalidation.gcmmplex.EVENT" />
+            </intent-filter>
+        </receiver>
+
         <provider android:name="org.chromium.chrome.browser.ChromeBrowserProvider"
                   android:authorities="org.chromium.chrome.shell"
                   android:exported="true" />

components/gcm_driver.gypi

@@ -107,6 +107,7 @@
           'type': 'none',
           'dependencies': [
             '../base/base.gyp:base',
+            '../sync/sync.gyp:sync_java',
           ],
           'variables': {
             'java_in_dir': 'gcm_driver/android/java',

components/gcm_driver/android/java/src/org/chromium/components/gcm_driver/GCMDriver.java

@@ -5,7 +5,11 @@
 package org.chromium.components.gcm_driver;
 
 import android.content.Context;
+import android.os.AsyncTask;
 import android.os.Bundle;
+import android.util.Log;
+
+import com.google.android.gcm.GCMRegistrar;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
@@ -15,11 +19,16 @@ import java.util.ArrayList;
 import java.util.List;
 
 /**
- * An implementation of GCMDriver using Android's Java GCM APIs.
+ * This class is the Java counterpart to the C++ GCMDriverAndroid class.
+ * It uses Android's Java GCM APIs to implements GCM registration etc, and
+ * sends back GCM messages over JNI.
+ *
  * Threading model: all calls to/from C++ happen on the UI thread.
  */
 @JNINamespace("gcm")
-public final class GCMDriver {
+public class GCMDriver {
+    private static final String TAG = "GCMDriver";
+
     // The instance of GCMDriver currently owned by a C++ GCMDriverAndroid, if any.
     private static GCMDriver sInstance = null;
 
@@ -41,8 +50,9 @@ public final class GCMDriver {
     @CalledByNative
     private static GCMDriver create(long nativeGCMDriverAndroid,
                                     Context context) {
-        if (sInstance != null)
+        if (sInstance != null) {
             throw new IllegalStateException("Already instantiated");
+        }
         sInstance = new GCMDriver(nativeGCMDriverAndroid, context);
         return sInstance;
     }
@@ -59,32 +69,91 @@ public final class GCMDriver {
     }
 
     @CalledByNative
-    private void register(String appId, String[] senderIds) {
-        // TODO(johnme): Actually try to register.
-        nativeOnRegisterFinished(mNativeGCMDriverAndroid, appId, "", false);
+    private void register(final String appId, final String[] senderIds) {
+        new AsyncTask<Void, Void, String>() {
+            @Override
+            protected String doInBackground(Void... voids) {
+                try {
+                    GCMRegistrar.checkDevice(mContext);
+                } catch (UnsupportedOperationException ex) {
+                    return ""; // Indicates failure.
+                }
+                // TODO(johnme): Move checkManifest call to a test instead.
+                GCMRegistrar.checkManifest(mContext);
+                String existingRegistrationId = GCMRegistrar.getRegistrationId(mContext);
+                if (existingRegistrationId.equals("")) {
+                    // TODO(johnme): Migrate from GCMRegistrar to GoogleCloudMessaging API, both
+                    // here and elsewhere in Chromium.
+                    // TODO(johnme): Pass appId to GCM.
+                    GCMRegistrar.register(mContext, senderIds);
+                    return null; // Indicates pending result.
+                } else {
+                    Log.i(TAG, "Re-using existing registration ID");
+                    return existingRegistrationId;
+                }
+            }
+            @Override
+            protected void onPostExecute(String registrationId) {
+                if (registrationId == null) {
+                    return; // Wait for {@link #onRegisterFinished} to be called.
+                }
+                nativeOnRegisterFinished(mNativeGCMDriverAndroid, appId, registrationId,
+                                         !registrationId.isEmpty());
+            }
+        }.execute();
     }
+
+    private enum UnregisterResult { SUCCESS, FAILED, PENDING }
+
     @CalledByNative
-    private void unregister(String appId) {
-        // TODO(johnme): Actually try to unregister.
-        nativeOnUnregisterFinished(mNativeGCMDriverAndroid, appId, false);
+    private void unregister(final String appId) {
+        new AsyncTask<Void, Void, UnregisterResult>() {
+            @Override
+            protected UnregisterResult doInBackground(Void... voids) {
+                try {
+                    GCMRegistrar.checkDevice(mContext);
+                } catch (UnsupportedOperationException ex) {
+                    return UnregisterResult.FAILED;
+                }
+                if (!GCMRegistrar.isRegistered(mContext)) {
+                    return UnregisterResult.SUCCESS;
+                }
+                // TODO(johnme): Pass appId to GCM.
+                GCMRegistrar.unregister(mContext);
+                return UnregisterResult.PENDING;
+            }
+
+            @Override
+            protected void onPostExecute(UnregisterResult result) {
+                if (result == UnregisterResult.PENDING) {
+                    return; // Wait for {@link #onUnregisterFinished} to be called.
+                }
+                nativeOnUnregisterFinished(mNativeGCMDriverAndroid, appId,
+                        result == UnregisterResult.SUCCESS);
+            }
+        }.execute();
     }
 
-    public static void onRegistered(String appId, String registrationId) {
+    static void onRegisterFinished(String appId, String registrationId) {
         ThreadUtils.assertOnUiThread();
+        // TODO(johnme): If this gets called, did it definitely succeed?
         // TODO(johnme): Update registrations cache?
-        if (sInstance != null)
+        if (sInstance != null) {
             sInstance.nativeOnRegisterFinished(sInstance.mNativeGCMDriverAndroid, appId,
                                                registrationId, true);
+        }
     }
 
-    public static void onUnregistered(String appId) {
+    static void onUnregisterFinished(String appId) {
         ThreadUtils.assertOnUiThread();
+        // TODO(johnme): If this gets called, did it definitely succeed?
         // TODO(johnme): Update registrations cache?
-        if (sInstance != null)
+        if (sInstance != null) {
             sInstance.nativeOnUnregisterFinished(sInstance.mNativeGCMDriverAndroid, appId, true);
+        }
     }
 
-    public static void onMessageReceived(final String appId, final Bundle extras) {
+    static void onMessageReceived(final String appId, final Bundle extras) {
         // TODO(johnme): Store message and redeliver later if Chrome is killed before delivery.
         ThreadUtils.assertOnUiThread();
         launchNativeThen(new Runnable() {
@@ -113,7 +182,7 @@ public final class GCMDriver {
         });
     }
 
-    public static void onMessagesDeleted(final String appId) {
+    static void onMessagesDeleted(final String appId) {
         // TODO(johnme): Store event and redeliver later if Chrome is killed before delivery.
         ThreadUtils.assertOnUiThread();
         launchNativeThen(new Runnable() {

components/gcm_driver/android/java/src/org/chromium/components/gcm_driver/GCMListener.java

+// Copyright 2014 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.components.gcm_driver;
+
+import android.content.Intent;
+
+import com.google.ipc.invalidation.external.client.contrib.MultiplexingGcmListener;
+
+import org.chromium.base.ThreadUtils;
+
+/**
+ * Receives GCM registration events and messages rebroadcast by MultiplexingGcmListener.
+ */
+public class GCMListener extends MultiplexingGcmListener.AbstractListener {
+    /**
+     * Receiver for broadcasts by the multiplexed GCM service. It forwards them to
+     * GCMListener.
+     *
+     * This class is public so that it can be instantiated by the Android runtime.
+     */
+    public static class Receiver extends MultiplexingGcmListener.AbstractListener.Receiver {
+        @Override
+        protected Class<?> getServiceClass() {
+            return GCMListener.class;
+        }
+    }
+
+    private static final String TAG = "GCMListener";
+
+    public GCMListener() {
+        super(TAG);
+    }
+
+    @Override
+    protected void onRegistered(final String registrationId) {
+        ThreadUtils.runOnUiThread(new Runnable() {
+            @Override public void run() {
+                // TODO(johnme): Get app ID.
+                GCMDriver.onRegisterFinished("unknown-app-id", registrationId);
+            }
+        });
+    }
+
+    @Override
+    protected void onUnregistered(String registrationId) {
+        ThreadUtils.runOnUiThread(new Runnable() {
+            @Override public void run() {
+                // TODO(johnme): Get app ID.
+                GCMDriver.onUnregisterFinished("unknown-app-id");
+            }
+        });
+    }
+
+    @Override
+    protected void onMessage(final Intent intent) {
+        ThreadUtils.runOnUiThread(new Runnable() {
+            @Override public void run() {
+                // TODO(johnme): Get app ID.
+                GCMDriver.onMessageReceived("unknown-app-id", intent.getExtras());
+            }
+        });
+    }
+
+    @Override
+    protected void onDeletedMessages(int total) {
+        ThreadUtils.runOnUiThread(new Runnable() {
+            @Override public void run() {
+                // TODO(johnme): Get app ID.
+                GCMDriver.onMessagesDeleted("unknown-app-id");
+            }
+        });
+    }
+}

sync/android/java/src/org/chromium/sync/SyncSwitches.java

+// Copyright 2014 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.sync;
+
+/**
+ * Contains all of the command line switches that are specific to the sync/
+ * portion of Chromium on Android.
+ */
+public abstract class SyncSwitches {
+    // It's currently necessary for people wanting to try out the Push API to disable Chrome Sync's
+    // use of GCM (as Android only grants a single registration ID, and they can't both use it).
+    // Accordingly, this switch lets you disable Sync's ability to receive GCM messages in order to
+    // make it possible to try out the Push API. Don't use this in production!
+    // TODO(johnme): Remove this command line switch once disabling sync is no longer necessary.
+    public static final String DISABLE_SYNC_GCM_IN_ORDER_TO_TRY_PUSH_API =
+            "disable-sync-gcm-in-order-to-try-push-api";
+
+    // Prevent instantiation.
+    private SyncSwitches() {}
+}

sync/android/java/src/org/chromium/sync/signin/ChromeSigninController.java

@@ -13,7 +13,9 @@ import android.util.Log;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.ipc.invalidation.external.client.contrib.MultiplexingGcmListener;
 
+import org.chromium.base.CommandLine;
 import org.chromium.base.ObserverList;
+import org.chromium.sync.SyncSwitches;
 
 public class ChromeSigninController {
     public interface Listener {
@@ -114,6 +116,11 @@ public class ChromeSigninController {
         new AsyncTask<Void, Void, Void>() {
             @Override
             protected Void doInBackground(Void... arg0) {
+                if (CommandLine.getInstance().hasSwitch(
+                        SyncSwitches.DISABLE_SYNC_GCM_IN_ORDER_TO_TRY_PUSH_API)) {
+                    Log.w(TAG, "Sync GCM notifications disabled in order to try Push API!");
+                    return null;
+                }
                 try {
                     String regId = MultiplexingGcmListener.initializeGcm(mApplicationContext);
                     if (!regId.isEmpty())