[Android] BackgroundTaskScheduler reschedule implementation

components/background_task_scheduler/android/junit/src/org/chromium/components/background_task_scheduler/BackgroundTaskGcmTaskServiceTest.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 static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 
 import android.content.Context;
 import android.os.Bundle;
 
 import com.google.android.gms.gcm.GcmNetworkManager;
 import com.google.android.gms.gcm.TaskParams;
 
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.annotation.Config;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.base.test.util.Feature;
 import org.chromium.testing.local.LocalRobolectricTestRunner;
 
+import java.util.concurrent.TimeUnit;
+
 /** Unit tests for {@link BackgroundTaskGcmTaskService}. */
 @RunWith(LocalRobolectricTestRunner.class)
 @Config(manifest = Config.NONE)
 public class BackgroundTaskGcmTaskServiceTest {
     static TestBackgroundTaskWithParams sLastTask;
     static boolean sReturnThroughCallback;
     static boolean sNeedsRescheduling;
+    @Mock
+    private BackgroundTaskSchedulerDelegate mDelegate;
 
     @Before
     public void setUp() {
+        MockitoAnnotations.initMocks(this);
         ContextUtils.initApplicationContextForTests(RuntimeEnvironment.application);
+        BackgroundTaskSchedulerFactory.setSchedulerForTesting(
+                new BackgroundTaskScheduler(mDelegate));
         sReturnThroughCallback = false;
         sNeedsRescheduling = false;
         sLastTask = null;
+        TestBackgroundTask.reset();
     }
 
     private static class TestBackgroundTaskWithParams extends TestBackgroundTask {
         private TaskParameters mTaskParameters;
 
         public TestBackgroundTaskWithParams() {}
 
         @Override
         public boolean onStartTask(
                 Context context, TaskParameters taskParameters, TaskFinishedCallback callback) {
@@ skipping 52 matching lines @@
     @Feature({"BackgroundTaskScheduler"})
     public void testOnRuntaskDontRescheduleFromCallback() {
         sReturnThroughCallback = true;
         sNeedsRescheduling = false;
         TaskParams taskParams = buildTaskParams(TestBackgroundTaskWithParams.class, new Bundle());
 
         BackgroundTaskGcmTaskService taskService = new BackgroundTaskGcmTaskService();
         assertEquals(taskService.onRunTask(taskParams), GcmNetworkManager.RESULT_SUCCESS);
     }
 
+    @Test
+    @Feature({"BackgroundTaskScheduler"})
+    public void testOnInitializeTasks() {
+        TaskInfo task = TaskInfo.createOneOffTask(TaskIds.TEST, TestBackgroundTask.class,
+                                        TimeUnit.DAYS.toMillis(1))
+                                .build();
+        BackgroundTaskSchedulerPrefs.addScheduledTask(task);
+        assertEquals(0, TestBackgroundTask.getRescheduleCalls());
+
+        BackgroundTaskGcmTaskService taskService = new BackgroundTaskGcmTaskService();
+        taskService.onInitializeTasks();
+        assertEquals(1, TestBackgroundTask.getRescheduleCalls());
+    }
+
     private TaskParams buildTaskParams(Class clazz, Bundle taskExtras) {
         Bundle extras = new Bundle();
         extras.putBundle(
                 BackgroundTaskSchedulerGcmNetworkManager.BACKGROUND_TASK_EXTRAS_KEY, taskExtras);
         extras.putString(BackgroundTaskSchedulerGcmNetworkManager.BACKGROUND_TASK_CLASS_KEY,
                 clazz.getName());
 
         return new TaskParams(Integer.toString(TaskIds.TEST), extras);
     }
 }