[Android] Adding scheduling through GcmNetworkManager

components/background_task_scheduler/android/java/src/org/chromium/components/background_task_scheduler/BackgroundTaskScheduler.java

 // Copyright 2017 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.background_task_scheduler;
 
 import android.annotation.TargetApi;
 import android.content.Context;
 import android.os.Build;
 import android.support.annotation.Nullable;
@@ skipping 57 matching lines @@
      * Schedules a background task. See {@link TaskInfo} for information on what types of tasks that
      * can be scheduled.
      *
      * @param context the current context.
      * @param taskInfo the information about the task to be scheduled.
      * @return true if the schedule operation succeeded, and false otherwise.
      * @see TaskInfo
      */
     public boolean schedule(Context context, TaskInfo taskInfo) {
         ThreadUtils.assertOnUiThread();
+        BackgroundTaskSchedulerPrefs.addScheduledTask(taskInfo);
         return mSchedulerDelegate.schedule(context, taskInfo);
     }
 
     /**
      * Cancels the task specified by the task ID.
      *
      * @param context the current context.
      * @param taskId the ID of the task to cancel. See {@link TaskIds} for a list.
      */
     public void cancel(Context context, int taskId) {
         ThreadUtils.assertOnUiThread();
+        BackgroundTaskSchedulerPrefs.removeScheduledTask(taskId);
         mSchedulerDelegate.cancel(context, taskId);
     }
 }