[OfflinePages] Do not start background loading on low-end devices if app has any visible Activities.

chrome/android/junit/src/org/chromium/chrome/browser/offlinepages/BackgroundOfflinerTaskTest.java

Index: chrome/android/junit/src/org/chromium/chrome/browser/offlinepages/BackgroundOfflinerTaskTest.java
diff --git a/chrome/android/junit/src/org/chromium/chrome/browser/offlinepages/BackgroundOfflinerTaskTest.java b/chrome/android/junit/src/org/chromium/chrome/browser/offlinepages/BackgroundOfflinerTaskTest.java
index e4d58c9bcd3321ec0209bdc81202f0171917463f..269f9300c2a6b52a08e3b9e1e3e974790b566be8 100644
--- a/chrome/android/junit/src/org/chromium/chrome/browser/offlinepages/BackgroundOfflinerTaskTest.java
+++ b/chrome/android/junit/src/org/chromium/chrome/browser/offlinepages/BackgroundOfflinerTaskTest.java
@@ -13,12 +13,17 @@ import static org.junit.Assert.assertTrue;
 import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.when;
 
+import android.app.Activity;
 import android.content.Context;
 import android.os.Bundle;
 
 import com.google.android.gms.gcm.Task;
 
+import org.chromium.base.ActivityState;
+import org.chromium.base.ApplicationStatus;
 import org.chromium.base.BaseChromiumApplication;
+import org.chromium.base.BaseSwitches;
+import org.chromium.base.CommandLine;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.test.util.Feature;
 import org.chromium.chrome.browser.ChromeBackgroundServiceWaiter;
@@ -44,6 +49,8 @@ public class BackgroundOfflinerTaskTest {
     private static final boolean REQUIRE_UNMETERED = true;
     private static final boolean POWER_CONNECTED = true;
     private static final int MINIMUM_BATTERY_LEVEL = 33;
+    private static final String IS_LOW_END_DEVICE_SWITCH =
+            "--" + BaseSwitches.ENABLE_LOW_END_DEVICE_MODE;
 
     @Mock
     private OfflinePageUtils mOfflinePageUtils;
@@ -71,6 +78,7 @@ public class BackgroundOfflinerTaskTest {
         mStubBackgroundSchedulerProcessor = new StubBackgroundSchedulerProcessor();
         RecordHistogram.disableForTests();
         ShadowGcmNetworkManager.clear();
+        CommandLine.init(new String[] {"testcommand", IS_LOW_END_DEVICE_SWITCH});
     }
 
     @Test
@@ -138,4 +146,32 @@ public class BackgroundOfflinerTaskTest {
         ChromeBackgroundServiceWaiter waiter2 = new ChromeBackgroundServiceWaiter(1);
         assertTrue(task2.startBackgroundRequests(Robolectric.application, mTaskExtras, waiter2));
     }
+
+    @Test
+    @Feature({"OfflinePages"})
+    public void testStartBackgroundRequestsForRunningActivityOnLowEndDevice() {
+        BackgroundOfflinerTask task = new BackgroundOfflinerTask(mStubBackgroundSchedulerProcessor);
+        ChromeBackgroundServiceWaiter waiter = new ChromeBackgroundServiceWaiter(1);
+        assertNull("Nothing scheduled", ShadowGcmNetworkManager.getScheduledTask());
+        Activity testActivity = new Activity();

[Pete Williamson, 2016/07/19 21:15:43]

Maybe add a comment here:

// Create another activity on the device, and use test methods to simulate it
being in a started state.

[dougarnett, 2016/07/19 21:29:06]

Done.

+        ApplicationStatus.onStateChangeForTesting(testActivity, ActivityState.CREATED);
+        ApplicationStatus.onStateChangeForTesting(testActivity, ActivityState.STARTED);
+        assertFalse(task.startBackgroundRequests(Robolectric.application, mTaskExtras, waiter));
+
+        // Check that the backup task was scheduled.
+        Task gcmTask = ShadowGcmNetworkManager.getScheduledTask();
+        assertNotNull("Backup task scheduled", gcmTask);
+        assertEquals(mTriggerConditions,
+                TaskExtrasPacker.unpackTriggerConditionsFromBundle(gcmTask.getExtras()));
+
+        // Check that startProcessing was NOT called.
+        assertFalse(mStubBackgroundSchedulerProcessor.getStartProcessingCalled());
+
+        // Now verify will start processing when Activity is stopped.
+        ApplicationStatus.onStateChangeForTesting(testActivity, ActivityState.STOPPED);
+        BackgroundOfflinerTask task2 =
+                new BackgroundOfflinerTask(mStubBackgroundSchedulerProcessor);
+        ChromeBackgroundServiceWaiter waiter2 = new ChromeBackgroundServiceWaiter(1);
+        assertTrue(task2.startBackgroundRequests(Robolectric.application, mTaskExtras, waiter2));
+    }
 }