[Android] Implements OS upgrade check and rescheduling

components/background_task_scheduler/android/junit/src/org/chromium/components/background_task_scheduler/BackgroundTaskSchedulerPrefsTest.java

Index: components/background_task_scheduler/android/junit/src/org/chromium/components/background_task_scheduler/BackgroundTaskSchedulerPrefsTest.java
diff --git a/components/background_task_scheduler/android/junit/src/org/chromium/components/background_task_scheduler/BackgroundTaskSchedulerPrefsTest.java b/components/background_task_scheduler/android/junit/src/org/chromium/components/background_task_scheduler/BackgroundTaskSchedulerPrefsTest.java
index 57426a92999b032d1672cb12db4cf3c0255a0725..e5d8ec76d22aba50d2b9e1985be04053eeed53e1 100644
--- a/components/background_task_scheduler/android/junit/src/org/chromium/components/background_task_scheduler/BackgroundTaskSchedulerPrefsTest.java
+++ b/components/background_task_scheduler/android/junit/src/org/chromium/components/background_task_scheduler/BackgroundTaskSchedulerPrefsTest.java
@@ -8,11 +8,14 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+import android.os.Build;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.annotation.Config;
+import org.robolectric.util.ReflectionHelpers;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.base.test.util.Feature;
@@ -65,6 +68,10 @@ public class BackgroundTaskSchedulerPrefsTest {
                 scheduledTasks.contains(TASK_1.getBackgroundTaskClass().getName()));
         assertTrue("TASK_2 class name in scheduled tasks.",
                 scheduledTasks.contains(TASK_2.getBackgroundTaskClass().getName()));
+
+        Set<Integer> taskIds = BackgroundTaskSchedulerPrefs.getScheduledTaskIds();
+        assertTrue(taskIds.contains(TASK_1.getTaskId()));
+        assertTrue(taskIds.contains(TASK_2.getTaskId()));
     }
 
     @Test
@@ -81,10 +88,14 @@ public class BackgroundTaskSchedulerPrefsTest {
                 BackgroundTaskSchedulerPrefs.getScheduledTasks().size());
 
         Set<String> scheduledTasks = BackgroundTaskSchedulerPrefs.getScheduledTasks();
-        assertFalse("TASK_1 class name in scheduled tasks.",
+        assertFalse("TASK_1 class name is not in scheduled tasks.",
                 scheduledTasks.contains(TASK_1.getBackgroundTaskClass().getName()));
         assertTrue("TASK_2 class name in scheduled tasks.",
                 scheduledTasks.contains(TASK_2.getBackgroundTaskClass().getName()));
+
+        Set<Integer> taskIds = BackgroundTaskSchedulerPrefs.getScheduledTaskIds();
+        assertFalse(taskIds.contains(TASK_1.getTaskId()));
+        assertTrue(taskIds.contains(TASK_2.getTaskId()));
     }
 
     @Test
@@ -95,5 +106,19 @@ public class BackgroundTaskSchedulerPrefsTest {
         BackgroundTaskSchedulerPrefs.removeAllTasks();
         assertTrue("We are expecting a all tasks to be gone.",
                 BackgroundTaskSchedulerPrefs.getScheduledTasks().isEmpty());
+        assertTrue("We are expecting a all tasks to be gone.",
+                BackgroundTaskSchedulerPrefs.getScheduledTaskIds().isEmpty());
+    }
+
+    @Test
+    @Feature("BackgroundTaskScheduler")
+    public void testLastSdkVersion() {
+        ReflectionHelpers.setStaticField(
+                Build.VERSION.class, "SDK_INT", Build.VERSION_CODES.KITKAT);
+        assertEquals("Current SDK version should be default.", Build.VERSION_CODES.KITKAT,
+                BackgroundTaskSchedulerPrefs.getLastSdkVersion());
+        BackgroundTaskSchedulerPrefs.setLastSdkVersion(Build.VERSION_CODES.LOLLIPOP);
+        assertEquals(
+                Build.VERSION_CODES.LOLLIPOP, BackgroundTaskSchedulerPrefs.getLastSdkVersion());
     }
 }