[Reland] Refactor WebappRegistry into a singleton instance.

chrome/android/java/src/org/chromium/chrome/browser/notifications/NotificationService.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.chrome.browser.notifications;
 
 import android.app.IntentService;
 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
+import android.os.StrictMode;
 import android.util.Log;
 
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.annotations.SuppressFBWarnings;
 import org.chromium.base.library_loader.ProcessInitException;
 import org.chromium.chrome.browser.init.ChromeBrowserInitializer;
+import org.chromium.chrome.browser.webapps.WebappRegistry;
 
 /**
  * The Notification service receives intents fired as responses to user actions issued on Android
  * notifications displayed in the notification tray.
  */
 public class NotificationService extends IntentService {
     private static final String TAG = NotificationService.class.getSimpleName();
 
     /**
      * The class which receives the intents from the Android framework. It initializes the
@@ skipping 42 matching lines @@
      * Initializes Chrome and starts the browser process if it's not running as of yet, and
      * dispatch |intent| to the NotificationPlatformBridge once this is done.
      *
      * @param intent The intent containing the notification's information.
      */
     @SuppressFBWarnings("DM_EXIT")
     private void dispatchIntentOnUIThread(Intent intent) {
         try {
             ChromeBrowserInitializer.getInstance(this).handleSynchronousStartup();
 
+            // Warm up the WebappRegistry and all web app SharedPreferences, as we will need check

[gone, 2016/09/29 21:06:44]

need to check

[dominickn, 2016/09/30 00:17:01]

Done.

+            // if this notification should launch a standalone web app. This no-ops if the registry
+            // is already initialized, but triggers a strict mode violation otherwise (i.e. the
+            // browser isn't running). Temporarily disable strict mode to work around the violation.
+            StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
+            try {
+                WebappRegistry.warmUpSharedPrefs("");
+            } finally {
+                StrictMode.setThreadPolicy(oldPolicy);
+            }
+
             // Now that the browser process is initialized, we pass forward the call to the
             // NotificationPlatformBridge which will take care of delivering the appropriate events.
             if (!NotificationPlatformBridge.dispatchNotificationEvent(intent)) {
                 Log.w(TAG, "Unable to dispatch the notification event to Chrome.");
             }
 
             // TODO(peter): Verify that the lifetime of the NotificationService is sufficient
             // when a notification event could be dispatched successfully.
 
         } catch (ProcessInitException e) {
             Log.e(TAG, "Unable to start the browser process.", e);
             System.exit(-1);
         }
     }
 }