[NTP Snippets] Schedule periodic fetching

BUG=586452

Review URL: https://codereview.chromium.org/1699143002

Cr-Commit-Position: refs/heads/master@{#377581}

21 files changed, 568 insertions, 165 deletions

diff --git a/chrome/android/java/AndroidManifest.xml b/chrome/android/java/AndroidManifest.xml
index 0ca1758..369ba35 100644
--- a/chrome/android/java/AndroidManifest.xml
+++ b/chrome/android/java/AndroidManifest.xml
@@ -579,8 +579,8 @@ by a child template that "extends" this file.
             </intent-filter>
         </receiver>
 
-        <!-- Service Worker Background Sync GCM scheduler task -->
-        <service android:name="org.chromium.chrome.browser.BackgroundSyncLauncherService"
+        <!-- GcmTaskService implementation to wake Chrome on scheduled events -->
+        <service android:name="org.chromium.chrome.browser.ChromeBackgroundService"
             android:permission="com.google.android.gms.permission.BIND_NETWORK_TASK_SERVICE"
             android:exported="true">
             <intent-filter>
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncher.java b/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncher.java
index ffec5a9..69537e4 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncher.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncher.java
@@ -30,6 +30,8 @@ import org.chromium.chrome.browser.externalauth.UserRecoverableErrorHandler;
 public class BackgroundSyncLauncher {
     private static final String TAG = "BgSyncLauncher";
 
+    public static final String TASK_TAG = "BackgroundSync Event";
+
     static final String PREF_BACKGROUND_SYNC_LAUNCH_NEXT_ONLINE = "bgsync_launch_next_online";
     // The instance of BackgroundSyncLauncher currently owned by a C++
     // BackgroundSyncLauncherAndroid, if any. If it is non-null then the browser is running.
@@ -191,8 +193,8 @@ public class BackgroundSyncLauncher {
         // the Play Store. In this case, scheduling the task will fail silently.
         final long minDelaySecs = minDelayMs / 1000;
         OneoffTask oneoff = new OneoffTask.Builder()
-                                    .setService(BackgroundSyncLauncherService.class)
-                                    .setTag("BackgroundSync Event")
+                                    .setService(ChromeBackgroundService.class)
+                                    .setTag(TASK_TAG)
                                     // We have to set a non-zero execution window here
                                     .setExecutionWindow(minDelaySecs, minDelaySecs + 1)
                                     .setRequiredNetwork(Task.NETWORK_STATE_CONNECTED)
@@ -212,7 +214,7 @@ public class BackgroundSyncLauncher {
 
     private static boolean removeScheduledTasks(GcmNetworkManager scheduler) {
         try {
-            scheduler.cancelAllTasks(BackgroundSyncLauncherService.class);
+            scheduler.cancelTask(TASK_TAG, ChromeBackgroundService.class);
         } catch (IllegalArgumentException e) {
             // This occurs when BackgroundSyncLauncherService is not found in the application
             // manifest. This should not happen in code that reaches here, but has been seen in
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncherService.java b/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncherService.java
deleted file mode 100644
index a6219fd..0000000
--- a/chrome/android/java/src/org/chromium/chrome/browser/BackgroundSyncLauncherService.java
+++ /dev/null
@@ -1,69 +0,0 @@
-// Copyright 2015 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;
-
-import android.content.Context;
-
-import com.google.android.gms.gcm.GcmNetworkManager;
-import com.google.android.gms.gcm.GcmTaskService;
-import com.google.android.gms.gcm.TaskParams;
-
-import org.chromium.base.Log;
-import org.chromium.base.ThreadUtils;
-import org.chromium.base.VisibleForTesting;
-import org.chromium.base.annotations.SuppressFBWarnings;
-import org.chromium.base.library_loader.LibraryProcessType;
-import org.chromium.base.library_loader.ProcessInitException;
-import org.chromium.content.app.ContentApplication;
-import org.chromium.content.browser.BrowserStartupController;
-
-/**
- * {@link BackgroundSyncLauncherService} is scheduled through the {@link GcmNetworkManager}
- * when the browser needs to be launched in response to changing network or power conditions.
- */
-public class BackgroundSyncLauncherService extends GcmTaskService {
-    private static final String TAG = "BgSyncLauncher";
-
-    @Override
-    @VisibleForTesting
-    public int onRunTask(TaskParams params) {
-        // Start the browser. The browser's BackgroundSyncManager (for the active profile) will
-        // start, check the network, and run any necessary sync events. This task runs with a wake
-        // lock, but has a three minute timeout, so we need to start the browser in its own task.
-        // TODO(jkarlin): Protect the browser sync event with a wake lock. See crbug.com/486020.
-        Log.v(TAG, "Starting Browser after coming online");
-        final Context context = this;
-        ThreadUtils.runOnUiThread(new Runnable() {
-            @Override
-            public void run() {
-                if (!BackgroundSyncLauncher.hasInstance()) {
-                    launchBrowser(context);
-                }
-            }
-        });
-        return GcmNetworkManager.RESULT_SUCCESS;
-    }
-
-    @VisibleForTesting
-    @SuppressFBWarnings("DM_EXIT")
-    protected void launchBrowser(Context context) {
-        ContentApplication.initCommandLine(context);
-        try {
-            BrowserStartupController.get(context, LibraryProcessType.PROCESS_BROWSER)
-                    .startBrowserProcessesSync(false);
-        } catch (ProcessInitException e) {
-            Log.e(TAG, "ProcessInitException while starting the browser process");
-            // Since the library failed to initialize nothing in the application
-            // can work, so kill the whole application not just the activity.
-            System.exit(-1);
-        }
-    }
-
-    @Override
-    @VisibleForTesting
-    public void onInitializeTasks() {
-        BackgroundSyncLauncher.rescheduleTasksOnUpgrade(this);
-    }
-}
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
index 7fe5a78..fb7f9206 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
@@ -89,7 +89,6 @@ import org.chromium.chrome.browser.metrics.StartupMetrics;
 import org.chromium.chrome.browser.metrics.UmaSessionStats;
 import org.chromium.chrome.browser.nfc.BeamController;
 import org.chromium.chrome.browser.nfc.BeamProvider;
-import org.chromium.chrome.browser.ntp.snippets.SnippetsController;
 import org.chromium.chrome.browser.offlinepages.OfflinePageUtils;
 import org.chromium.chrome.browser.omaha.UpdateMenuItemHelper;
 import org.chromium.chrome.browser.pageinfo.WebsiteSettingsPopup;
@@ -694,12 +693,6 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
             mToolbarManager.onDeferredStartup(getOnCreateTimestampMs(), simpleName);
         }
         recordKeyboardLocaleUma();
-
-        // TODO(treib): Remove this when we have the proper morning reads fetching logic in place
-        if (ChromeFeatureList.isEnabled(ChromeFeatureList.NTP_SNIPPETS)) {
-            // Initialize snippets
-            SnippetsController.get(this).fetchSnippets(false);
-        }
     }
 
     @Override
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java b/chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java
new file mode 100644
index 0000000..7828402
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java
@@ -0,0 +1,101 @@
+// Copyright 2016 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;
+
+import android.content.Context;
+
+import com.google.android.gms.gcm.GcmNetworkManager;
+import com.google.android.gms.gcm.GcmTaskService;
+import com.google.android.gms.gcm.TaskParams;
+
+import org.chromium.base.Log;
+import org.chromium.base.ThreadUtils;
+import org.chromium.base.VisibleForTesting;
+import org.chromium.base.annotations.SuppressFBWarnings;
+import org.chromium.base.library_loader.LibraryProcessType;
+import org.chromium.base.library_loader.ProcessInitException;
+import org.chromium.chrome.browser.ntp.snippets.SnippetsController;
+import org.chromium.chrome.browser.ntp.snippets.SnippetsLauncher;
+import org.chromium.content.app.ContentApplication;
+import org.chromium.content.browser.BrowserStartupController;
+
+/**
+ * {@link ChromeBackgroundService} is scheduled through the {@link GcmNetworkManager} when the
+ * browser needs to be launched for scheduled tasks, or in response to changing network or power
+ * conditions.
+ */
+public class ChromeBackgroundService extends GcmTaskService {
+    private static final String TAG = "BackgroundService";
+
+    @Override
+    public int onRunTask(TaskParams params) {
+        Log.i(TAG, "Woken up at " + new java.util.Date().toString());
+        handleRunTask(params.getTag());
+        return GcmNetworkManager.RESULT_SUCCESS;
+    }
+
+    @VisibleForTesting
+    public void handleRunTask(final String tag) {
+        final Context context = this;
+        ThreadUtils.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                switch(tag) {
+                    case BackgroundSyncLauncher.TASK_TAG:
+                        handleBackgroundSyncEvent(context);
+                        break;
+
+                    case SnippetsLauncher.TASK_TAG:
+                        handleFetchSnippets(context);
+                        break;
+
+                    default:
+                        Log.i(TAG, "Unknown task tag " + tag);
+                        break;
+                }
+            }
+        });
+    }
+
+    private void handleBackgroundSyncEvent(Context context) {
+        if (!BackgroundSyncLauncher.hasInstance()) {
+            // Start the browser. The browser's BackgroundSyncManager (for the active profile) will
+            // start, check the network, and run any necessary sync events. This task runs with a
+            // wake lock, but has a three minute timeout, so we need to start the browser in its
+            // own task.
+            // TODO(jkarlin): Protect the browser sync event with a wake lock.
+            // See crbug.com/486020.
+            launchBrowser(context);
+        }
+    }
+
+    private void handleFetchSnippets(Context context) {
+        if (!SnippetsLauncher.hasInstance()) {
+            launchBrowser(context);
+        }
+        SnippetsController.get(context).fetchSnippets(true);
+    }
+
+    @VisibleForTesting
+    @SuppressFBWarnings("DM_EXIT")
+    protected void launchBrowser(Context context) {
+        Log.i(TAG, "Launching browser");
+        ContentApplication.initCommandLine(context);
+        try {
+            BrowserStartupController.get(context, LibraryProcessType.PROCESS_BROWSER)
+                    .startBrowserProcessesSync(false);
+        } catch (ProcessInitException e) {
+            Log.e(TAG, "ProcessInitException while starting the browser process");
+            // Since the library failed to initialize nothing in the application
+            // can work, so kill the whole application not just the activity.
+            System.exit(-1);
+        }
+    }
+
+    @Override
+    public void onInitializeTasks() {
+        BackgroundSyncLauncher.rescheduleTasksOnUpgrade(this);
+    }
+}
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsController.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsController.java
index 55dd84c..e11d187 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsController.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsController.java
@@ -7,6 +7,7 @@ package org.chromium.chrome.browser.ntp.snippets;
 import android.content.Context;
 
 import org.chromium.base.ThreadUtils;
+import org.chromium.base.VisibleForTesting;
 import org.chromium.chrome.browser.profiles.Profile;
 import org.chromium.chrome.browser.signin.SigninManager;
 import org.chromium.chrome.browser.signin.SigninManager.SignInStateObserver;
@@ -20,7 +21,10 @@ public class SnippetsController implements SignInStateObserver {
     private long mNativeSnippetsController;
 
     public SnippetsController(Context applicationContext) {
-        SigninManager.get(applicationContext).addSignInStateObserver(this);
+        // |applicationContext| can be null in tests.
+        if (applicationContext != null) {
+            SigninManager.get(applicationContext).addSignInStateObserver(this);
+        }
     }
 
     /**
@@ -55,5 +59,10 @@ public class SnippetsController implements SignInStateObserver {
     @Override
     public void onSignedOut() {}
 
+    @VisibleForTesting
+    public static void setInstanceForTesting(SnippetsController instance) {
+        sInstance = instance;
+    }
+
     private native void nativeFetchSnippets(Profile profile, boolean overwrite);
 }
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsLauncher.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsLauncher.java
new file mode 100644
index 0000000..18ad921
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsLauncher.java
@@ -0,0 +1,132 @@
+// Copyright 2016 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.ntp.snippets;
+
+import android.content.Context;
+
+import com.google.android.gms.gcm.GcmNetworkManager;
+import com.google.android.gms.gcm.PeriodicTask;
+import com.google.android.gms.gcm.Task;
+
+import org.chromium.base.Log;
+import org.chromium.base.VisibleForTesting;
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.SuppressFBWarnings;
+import org.chromium.chrome.browser.ChromeBackgroundService;
+import org.chromium.chrome.browser.externalauth.ExternalAuthUtils;
+import org.chromium.chrome.browser.externalauth.UserRecoverableErrorHandler;
+
+/**
+ * The {@link SnippetsLauncher} singleton is created and owned by the C++ browser.
+ *
+ * Thread model: This class is to be run on the UI thread only.
+ */
+public class SnippetsLauncher {
+    private static final String TAG = "SnippetsLauncher";
+
+    public static final String TASK_TAG = "FetchSnippets";
+
+    // The instance of SnippetsLauncher currently owned by a C++ SnippetsLauncherAndroid, if any.
+    // If it is non-null then the browser is running.
+    private static SnippetsLauncher sInstance;
+
+    private GcmNetworkManager mScheduler;
+
+    private boolean mGCMEnabled = true;
+
+    /**
+     * Create a SnippetsLauncher object, which is owned by C++.
+     * @param context The app context.
+     */
+    @VisibleForTesting
+    @CalledByNative
+    public static SnippetsLauncher create(Context context) {
+        if (sInstance != null) {
+            throw new IllegalStateException("Already instantiated");
+        }
+
+        sInstance = new SnippetsLauncher(context);
+        return sInstance;
+    }
+
+    /**
+     * Called when the C++ counterpart is deleted.
+     */
+    @VisibleForTesting
+    @SuppressFBWarnings("ST_WRITE_TO_STATIC_FROM_INSTANCE_METHOD")
+    @CalledByNative
+    public void destroy() {
+        assert sInstance == this;
+        sInstance = null;
+    }
+
+    /**
+     * Returns true if the native browser has started and created an instance of {@link
+     * SnippetsLauncher}.
+     */
+    public static boolean hasInstance() {
+        return sInstance != null;
+    }
+
+    protected SnippetsLauncher(Context context) {
+        checkGCM(context);
+        mScheduler = GcmNetworkManager.getInstance(context);
+    }
+
+    private boolean canUseGooglePlayServices(Context context) {
+        return ExternalAuthUtils.getInstance().canUseGooglePlayServices(
+                context, new UserRecoverableErrorHandler.Silent());
+    }
+
+    private void checkGCM(Context context) {
+        // Check to see if Play Services is up to date, and disable GCM if not.
+        if (!canUseGooglePlayServices(context)) {
+            mGCMEnabled = false;
+            Log.i(TAG, "Disabling SnippetsLauncher because Play Services is not up to date.");
+        }
+    }
+
+    @CalledByNative
+    private boolean schedule(int periodSeconds) {
+        if (!mGCMEnabled) return false;
+        Log.i(TAG, "Scheduling: " + periodSeconds);
+        // Google Play Services may not be up to date, if the application was not installed through
+        // the Play Store. In this case, scheduling the task will fail silently.
+        PeriodicTask task = new PeriodicTask.Builder()
+                                    .setService(ChromeBackgroundService.class)
+                                    .setTag(TASK_TAG)
+                                    .setPeriod(periodSeconds)
+                                    .setRequiredNetwork(Task.NETWORK_STATE_UNMETERED)
+                                    .setPersisted(true)
+                                    .setUpdateCurrent(true)
+                                    .build();
+        try {
+            mScheduler.schedule(task);
+        } catch (IllegalArgumentException e) {
+            // Disable GCM for the remainder of this session.
+            mGCMEnabled = false;
+            // Return false so that the failure will be logged.
+            return false;
+        }
+        return true;
+    }
+
+    @CalledByNative
+    private boolean unschedule() {
+        if (!mGCMEnabled) return false;
+        Log.i(TAG, "Unscheduling");
+        try {
+            mScheduler.cancelTask("SnippetsLauncher", ChromeBackgroundService.class);
+        } catch (IllegalArgumentException e) {
+            // This occurs when SnippetsLauncherService is not found in the application
+            // manifest. Disable GCM for the remainder of this session.
+            mGCMEnabled = false;
+            // Return false so that the failure will be logged.
+            return false;
+        }
+        return true;
+    }
+}
+
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/BackgroundSyncLauncherServiceTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/BackgroundSyncLauncherServiceTest.java
deleted file mode 100644
index e626c25..0000000
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/BackgroundSyncLauncherServiceTest.java
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright 2015 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;
-
-import android.content.Context;
-import android.test.InstrumentationTestCase;
-import android.test.suitebuilder.annotation.SmallTest;
-
-import org.chromium.base.ThreadUtils;
-import org.chromium.base.metrics.RecordHistogram;
-import org.chromium.base.test.util.AdvancedMockContext;
-import org.chromium.base.test.util.Feature;
-
-/**
- * Tests {@link BackgroundSyncLauncherService}.
- */
-public class BackgroundSyncLauncherServiceTest extends InstrumentationTestCase {
-    private Context mContext;
-    private BackgroundSyncLauncher mLauncher;
-    private MockLauncherService mLauncherService;
-
-    static class MockLauncherService extends BackgroundSyncLauncherService {
-        private boolean mDidStartService = false;
-
-        @Override
-        protected void launchBrowser(Context context) {
-            mDidStartService = true;
-        }
-
-        // Posts an assertion task to the UI thread. Since this is only called after the call
-        // to onRunTask, it will be enqueued after any possible call to launchBrowser, and we
-        // can reliably check whether launchBrowser was called.
-        protected void checkExpectations(final boolean expectedStartService) {
-            ThreadUtils.runOnUiThread(new Runnable() {
-                @Override
-                public void run() {
-                    assertEquals("StartedService", expectedStartService, mDidStartService);
-                }
-            });
-        }
-    }
-
-    @Override
-    protected void setUp() throws Exception {
-        mContext = new AdvancedMockContext(getInstrumentation().getTargetContext());
-        BackgroundSyncLauncher.setGCMEnabled(false);
-        RecordHistogram.disableForTests();
-        mLauncher = BackgroundSyncLauncher.create(mContext);
-        mLauncherService = new MockLauncherService();
-    }
-
-    private void deleteLauncherInstance() {
-        mLauncher.destroy();
-        mLauncher = null;
-    }
-
-    private void startOnRunTaskAndVerify(boolean shouldStart) {
-        mLauncherService.onRunTask(null);
-        mLauncherService.checkExpectations(shouldStart);
-    }
-
-    @SmallTest
-    @Feature({"BackgroundSync"})
-    public void testNoFireWhenInstanceExists() {
-        startOnRunTaskAndVerify(false);
-    }
-
-    @SmallTest
-    @Feature({"BackgroundSync"})
-    public void testFiresWhenInstanceDoesNotExist() {
-        deleteLauncherInstance();
-        startOnRunTaskAndVerify(true);
-    }
-}
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java
new file mode 100644
index 0000000..fb25f1f
--- /dev/null
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java
@@ -0,0 +1,125 @@
+// Copyright 2016 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;
+
+import android.content.Context;
+import android.test.InstrumentationTestCase;
+import android.test.suitebuilder.annotation.SmallTest;
+
+import org.chromium.base.ThreadUtils;
+import org.chromium.base.metrics.RecordHistogram;
+import org.chromium.base.test.util.AdvancedMockContext;
+import org.chromium.base.test.util.Feature;
+import org.chromium.chrome.browser.ntp.snippets.SnippetsController;
+import org.chromium.chrome.browser.ntp.snippets.SnippetsLauncher;
+
+/**
+ * Tests {@link ChromeBackgroundService}.
+ */
+public class ChromeBackgroundServiceTest extends InstrumentationTestCase {
+    private Context mContext;
+    private BackgroundSyncLauncher mSyncLauncher;
+    private SnippetsLauncher mSnippetsLauncher;
+    private MockSnippetsController mSnippetsController;
+    private MockTaskService mTaskService;
+
+    static class MockTaskService extends ChromeBackgroundService {
+        private boolean mDidLaunchBrowser = false;
+
+        @Override
+        protected void launchBrowser(Context context) {
+            mDidLaunchBrowser = true;
+        }
+
+        // Posts an assertion task to the UI thread. Since this is only called after the call
+        // to onRunTask, it will be enqueued after any possible call to launchBrowser, and we
+        // can reliably check whether launchBrowser was called.
+        protected void checkExpectations(final boolean expectedLaunchBrowser) {
+            ThreadUtils.runOnUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    assertEquals("StartedService", expectedLaunchBrowser, mDidLaunchBrowser);
+                }
+            });
+        }
+    }
+
+    static class MockSnippetsController extends SnippetsController {
+        private boolean mDidFetchSnippets = false;
+
+        MockSnippetsController() {
+            super(null);
+        }
+
+        @Override
+        public void fetchSnippets(boolean overwrite) {
+            mDidFetchSnippets = true;
+        }
+
+        protected void checkExpectations(final boolean expectedFetchSnippets) {
+            ThreadUtils.runOnUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    assertEquals("FetchedSnippets", expectedFetchSnippets, mDidFetchSnippets);
+                }
+            });
+        }
+    }
+
+    @Override
+    protected void setUp() throws Exception {
+        mContext = new AdvancedMockContext(getInstrumentation().getTargetContext());
+        BackgroundSyncLauncher.setGCMEnabled(false);
+        RecordHistogram.disableForTests();
+        mSyncLauncher = BackgroundSyncLauncher.create(mContext);
+        mSnippetsLauncher = SnippetsLauncher.create(mContext);
+        mSnippetsController = new MockSnippetsController();
+        SnippetsController.setInstanceForTesting(mSnippetsController);
+        mTaskService = new MockTaskService();
+    }
+
+    private void deleteSyncLauncherInstance() {
+        mSyncLauncher.destroy();
+        mSyncLauncher = null;
+    }
+
+    private void deleteSnippetsLauncherInstance() {
+        mSnippetsLauncher.destroy();
+        mSnippetsLauncher = null;
+    }
+
+    private void startOnRunTaskAndVerify(String taskTag, boolean shouldStart,
+            boolean shouldFetchSnippets) {
+        mTaskService.handleRunTask(taskTag);
+        mTaskService.checkExpectations(shouldStart);
+        mSnippetsController.checkExpectations(shouldFetchSnippets);
+    }
+
+    @SmallTest
+    @Feature({"BackgroundSync"})
+    public void testBackgroundSyncNoLaunchBrowserWhenInstanceExists() {
+        startOnRunTaskAndVerify(BackgroundSyncLauncher.TASK_TAG, false, false);
+    }
+
+    @SmallTest
+    @Feature({"BackgroundSync"})
+    public void testBackgroundSyncLaunchBrowserWhenInstanceDoesNotExist() {
+        deleteSyncLauncherInstance();
+        startOnRunTaskAndVerify(BackgroundSyncLauncher.TASK_TAG, true, false);
+    }
+
+    @SmallTest
+    @Feature({"NTPSnippets"})
+    public void testNTPSnippetsNoLaunchBrowserWhenInstanceExists() {
+        startOnRunTaskAndVerify(SnippetsLauncher.TASK_TAG, false, true);
+    }
+
+    @SmallTest
+    @Feature({"NTPSnippets"})
+    public void testNTPSnippetsLaunchBrowserWhenInstanceDoesNotExist() {
+        deleteSnippetsLauncherInstance();
+        startOnRunTaskAndVerify(SnippetsLauncher.TASK_TAG, true, true);
+    }
+}
diff --git a/chrome/browser/android/chrome_jni_registrar.cc b/chrome/browser/android/chrome_jni_registrar.cc
index 8aca352..ddf0b94 100644
--- a/chrome/browser/android/chrome_jni_registrar.cc
+++ b/chrome/browser/android/chrome_jni_registrar.cc
@@ -62,6 +62,7 @@
 #include "chrome/browser/android/new_tab_page_prefs.h"
 #include "chrome/browser/android/ntp_snippets_bridge.h"
 #include "chrome/browser/android/ntp_snippets_controller.h"
+#include "chrome/browser/android/ntp_snippets_launcher.h"
 #include "chrome/browser/android/offline_pages/offline_page_bridge.h"
 #include "chrome/browser/android/omnibox/answers_image_bridge.h"
 #include "chrome/browser/android/omnibox/autocomplete_controller_android.h"
@@ -310,6 +311,7 @@ static base::android::RegistrationMethod kChromeRegisteredMethods[] = {
      NotificationUIManagerAndroid::RegisterNotificationUIManager},
     {"NTPSnippetsBridge", NTPSnippetsBridge::Register},
     {"NTPSnippetsController", NTPSnippetsController::Register},
+    {"NTPSnippetsLauncher", NTPSnippetsLauncher::Register},
     {"OAuth2TokenServiceDelegateAndroid",
      OAuth2TokenServiceDelegateAndroid::Register},
     {"OfflinePageBridge", offline_pages::android::RegisterOfflinePageBridge},
diff --git a/chrome/browser/android/ntp_snippets_launcher.cc b/chrome/browser/android/ntp_snippets_launcher.cc
new file mode 100644
index 0000000..3b05465
--- /dev/null
+++ b/chrome/browser/android/ntp_snippets_launcher.cc
@@ -0,0 +1,60 @@
+// Copyright 2016 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.
+
+#include "chrome/browser/android/ntp_snippets_launcher.h"
+
+#include "base/android/context_utils.h"
+#include "content/public/browser/browser_thread.h"
+#include "jni/SnippetsLauncher_jni.h"
+
+using content::BrowserThread;
+
+namespace {
+
+base::LazyInstance<NTPSnippetsLauncher> g_snippets_launcher =
+    LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
+// static
+NTPSnippetsLauncher* NTPSnippetsLauncher::Get() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  return g_snippets_launcher.Pointer();
+}
+
+// static
+bool NTPSnippetsLauncher::Register(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+bool NTPSnippetsLauncher::Schedule(int period_seconds) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  JNIEnv* env = base::android::AttachCurrentThread();
+  return Java_SnippetsLauncher_schedule(
+      env, java_launcher_.obj(), period_seconds);
+}
+
+bool NTPSnippetsLauncher::Unschedule() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  JNIEnv* env = base::android::AttachCurrentThread();
+  return Java_SnippetsLauncher_unschedule(env, java_launcher_.obj());
+}
+
+NTPSnippetsLauncher::NTPSnippetsLauncher() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  JNIEnv* env = base::android::AttachCurrentThread();
+  java_launcher_.Reset(Java_SnippetsLauncher_create(
+      env, base::android::GetApplicationContext()));
+}
+
+NTPSnippetsLauncher::~NTPSnippetsLauncher() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  JNIEnv* env = base::android::AttachCurrentThread();
+  Java_SnippetsLauncher_destroy(env, java_launcher_.obj());
+  java_launcher_.Reset();
+}
diff --git a/chrome/browser/android/ntp_snippets_launcher.h b/chrome/browser/android/ntp_snippets_launcher.h
new file mode 100644
index 0000000..c2f4ef6
--- /dev/null
+++ b/chrome/browser/android/ntp_snippets_launcher.h
@@ -0,0 +1,38 @@
+// Copyright 2016 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.
+
+#ifndef CHROME_BROWSER_ANDROID_NTP_SNIPPETS_LAUNCHER_H_
+#define CHROME_BROWSER_ANDROID_NTP_SNIPPETS_LAUNCHER_H_
+
+#include "base/android/jni_android.h"
+#include "base/lazy_instance.h"
+#include "base/macros.h"
+#include "components/ntp_snippets/ntp_snippets_scheduler.h"
+
+// Android implementation of ntp_snippets::NTPSnippetsScheduler.
+// The NTPSnippetsLauncher singleton owns the Java SnippetsLauncher object, and
+// is used to schedule the fetching of snippets. Runs on the UI thread.
+class NTPSnippetsLauncher : public ntp_snippets::NTPSnippetsScheduler {
+ public:
+  static NTPSnippetsLauncher* Get();
+
+  static bool Register(JNIEnv* env);
+
+  // ntp_snippets::NTPSnippetsScheduler implementation.
+  bool Schedule(int period_seconds) override;
+  bool Unschedule() override;
+
+ private:
+  friend struct base::DefaultLazyInstanceTraits<NTPSnippetsLauncher>;
+
+  // Constructor and destructor marked private to enforce singleton.
+  NTPSnippetsLauncher();
+  virtual ~NTPSnippetsLauncher();
+
+  base::android::ScopedJavaGlobalRef<jobject> java_launcher_;
+
+  DISALLOW_COPY_AND_ASSIGN(NTPSnippetsLauncher);
+};
+
+#endif  // CHROME_BROWSER_ANDROID_NTP_SNIPPETS_LAUNCHER_H_
diff --git a/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc b/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc
index 0cf2dba..50a2294 100644
--- a/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc
+++ b/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc
@@ -12,6 +12,7 @@
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/ntp_snippets/ntp_snippets_fetcher.h"
+#include "components/ntp_snippets/ntp_snippets_scheduler.h"
 #include "components/ntp_snippets/ntp_snippets_service.h"
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/signin/core/browser/signin_manager.h"
@@ -19,6 +20,10 @@
 #include "content/public/browser/browser_thread.h"
 #include "net/url_request/url_request_context_getter.h"
 
+#if defined(OS_ANDROID)
+#include "chrome/browser/android/ntp_snippets_launcher.h"
+#endif  // OS_ANDROID
+
 using content::BrowserThread;
 
 // static
@@ -51,6 +56,11 @@ KeyedService* NTPSnippetsServiceFactory::BuildServiceInstanceFor(
   scoped_refptr<net::URLRequestContextGetter> request_context =
       context->GetRequestContext();
 
+  ntp_snippets::NTPSnippetsScheduler* scheduler = nullptr;
+#if defined(OS_ANDROID)
+  scheduler = NTPSnippetsLauncher::Get();
+#endif  // OS_ANDROID
+
   scoped_refptr<base::SequencedTaskRunner> task_runner =
       BrowserThread::GetBlockingPool()
           ->GetSequencedTaskRunnerWithShutdownBehavior(
@@ -58,7 +68,7 @@ KeyedService* NTPSnippetsServiceFactory::BuildServiceInstanceFor(
               base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN);
 
   return new ntp_snippets::NTPSnippetsService(
-      task_runner, g_browser_process->GetApplicationLocale(),
+      task_runner, g_browser_process->GetApplicationLocale(), scheduler,
       make_scoped_ptr(new ntp_snippets::NTPSnippetsFetcher(
           task_runner, signin_manager, token_service, request_context,
           profile->GetPath())));
diff --git a/chrome/browser/profiles/profile_manager.cc b/chrome/browser/profiles/profile_manager.cc
index 11d852b..a5de323 100644
--- a/chrome/browser/profiles/profile_manager.cc
+++ b/chrome/browser/profiles/profile_manager.cc
@@ -12,6 +12,7 @@
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/deferred_sequenced_task_runner.h"
+#include "base/feature_list.h"
 #include "base/files/file_enumerator.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
@@ -106,8 +107,10 @@
 #include "chrome/browser/supervised_user/supervised_user_service_factory.h"
 #endif
 
-#if defined(OS_WIN)
-#include "chrome/installer/util/browser_distribution.h"
+#if defined(OS_ANDROID)
+#include "chrome/browser/android/chrome_feature_list.h"
+#include "chrome/browser/ntp_snippets/ntp_snippets_service_factory.h"
+#include "components/ntp_snippets/ntp_snippets_service.h"
 #endif
 
 #if defined(OS_CHROMEOS)
@@ -1150,6 +1153,14 @@ void ProfileManager::DoFinalInitForServices(Profile* profile,
   // migration code, rough time estimates are Q1 2016.
   PasswordManagerSettingMigratorServiceFactory::GetForProfile(profile)
       ->InitializeMigration(ProfileSyncServiceFactory::GetForProfile(profile));
+
+#if defined(OS_ANDROID)
+  // Service is responsible for fetching content snippets for the NTP.
+  // Note: Create the service even if the feature is disabled, so that any
+  // remaining tasks will be cleaned up.
+  NTPSnippetsServiceFactory::GetForProfile(profile)->Init(
+      base::FeatureList::IsEnabled(chrome::android::kNTPSnippetsFeature));
+#endif
 }
 
 void ProfileManager::DoFinalInitLogging(Profile* profile) {
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 5dfafa9..d7aec55 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -837,6 +837,8 @@
       'browser/android/ntp_snippets_bridge.h',
       'browser/android/ntp_snippets_controller.cc',
       'browser/android/ntp_snippets_controller.h',
+      'browser/android/ntp_snippets_launcher.cc',
+      'browser/android/ntp_snippets_launcher.h',
       'browser/android/omnibox/answers_image_bridge.cc',
       'browser/android/omnibox/answers_image_bridge.h',
       'browser/android/omnibox/autocomplete_controller_android.cc',
@@ -1891,6 +1893,7 @@
       'android/java/src/org/chromium/chrome/browser/ntp/RecentlyClosedBridge.java',
       'android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsBridge.java',
       'android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsController.java',
+      'android/java/src/org/chromium/chrome/browser/ntp/snippets/SnippetsLauncher.java',
       'android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageBridge.java',
       'android/java/src/org/chromium/chrome/browser/omnibox/AnswersImage.java',
       'android/java/src/org/chromium/chrome/browser/omnibox/AutocompleteController.java',
diff --git a/components/ntp_snippets.gypi b/components/ntp_snippets.gypi
index 551d3e6..d6a0d63 100644
--- a/components/ntp_snippets.gypi
+++ b/components/ntp_snippets.gypi
@@ -22,6 +22,7 @@
         'ntp_snippets/ntp_snippet.h',
         'ntp_snippets/ntp_snippets_fetcher.cc',
         'ntp_snippets/ntp_snippets_fetcher.h',
+        'ntp_snippets/ntp_snippets_scheduler.h',
         'ntp_snippets/ntp_snippets_service.cc',
         'ntp_snippets/ntp_snippets_service.h',
       ],
diff --git a/components/ntp_snippets/ntp_snippets_scheduler.h b/components/ntp_snippets/ntp_snippets_scheduler.h
new file mode 100644
index 0000000..afa60d9
--- /dev/null
+++ b/components/ntp_snippets/ntp_snippets_scheduler.h
@@ -0,0 +1,32 @@
+// Copyright 2016 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.
+
+#ifndef COMPONENTS_NTP_SNIPPETS_NTP_SNIPPETS_SCHEDULER_H_
+#define COMPONENTS_NTP_SNIPPETS_NTP_SNIPPETS_SCHEDULER_H_
+
+#include "base/macros.h"
+
+namespace ntp_snippets {
+
+// Interface to schedule the periodic fetching of snippets.
+class NTPSnippetsScheduler {
+ public:
+  // Schedule periodic fetching of snippets every |period_seconds|. The
+  // concrete implementation should call NTPSnippetsService::FetchSnippets once
+  // per period.
+  virtual bool Schedule(int period_seconds) = 0;
+
+  // Cancel the scheduled fetching task, if any.
+  virtual bool Unschedule() = 0;
+
+ protected:
+  NTPSnippetsScheduler() = default;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(NTPSnippetsScheduler);
+};
+
+}  // namespace ntp_snippets
+
+#endif  // COMPONENTS_NTP_SNIPPETS_NTP_SNIPPETS_SCHEDULER_H_
diff --git a/components/ntp_snippets/ntp_snippets_service.cc b/components/ntp_snippets/ntp_snippets_service.cc
index 149ab4a..fd031e3 100644
--- a/components/ntp_snippets/ntp_snippets_service.cc
+++ b/components/ntp_snippets/ntp_snippets_service.cc
@@ -12,7 +12,11 @@
 #include "base/task_runner_util.h"
 #include "base/values.h"
 
-namespace ntp_snippets {
+namespace {
+
+// TODO(crbug.com/587857): This is an extremely small value, for development.
+// Replace it by something sensible and add a command line param to control it.
+const int kDefaultFetchingIntervalSeconds = 60;
 
 bool ReadFileToString(const base::FilePath& path, std::string* data) {
   DCHECK(data);
@@ -21,13 +25,19 @@ bool ReadFileToString(const base::FilePath& path, std::string* data) {
   return success;
 }
 
+}  // namespace
+
+namespace ntp_snippets {
+
 NTPSnippetsService::NTPSnippetsService(
     scoped_refptr<base::SequencedTaskRunner> file_task_runner,
     const std::string& application_language_code,
+    NTPSnippetsScheduler* scheduler,
     scoped_ptr<NTPSnippetsFetcher> snippets_fetcher)
     : loaded_(false),
       file_task_runner_(file_task_runner),
       application_language_code_(application_language_code),
+      scheduler_(scheduler),
       snippets_fetcher_(std::move(snippets_fetcher)),
       weak_ptr_factory_(this) {
   snippets_fetcher_callback_ = snippets_fetcher_->AddCallback(
@@ -37,6 +47,17 @@ NTPSnippetsService::NTPSnippetsService(
 
 NTPSnippetsService::~NTPSnippetsService() {}
 
+void NTPSnippetsService::Init(bool enabled) {
+  // The scheduler only exists on Android so far, it's null on other platforms.
+  if (!scheduler_)
+    return;
+
+  if (enabled)
+    scheduler_->Schedule(kDefaultFetchingIntervalSeconds);
+  else
+    scheduler_->Unschedule();
+}
+
 void NTPSnippetsService::Shutdown() {
   FOR_EACH_OBSERVER(NTPSnippetsServiceObserver, observers_,
                     NTPSnippetsServiceShutdown(this));
diff --git a/components/ntp_snippets/ntp_snippets_service.h b/components/ntp_snippets/ntp_snippets_service.h
index f9d2a40..1b46bad 100644
--- a/components/ntp_snippets/ntp_snippets_service.h
+++ b/components/ntp_snippets/ntp_snippets_service.h
@@ -18,6 +18,7 @@
 #include "components/ntp_snippets/inner_iterator.h"
 #include "components/ntp_snippets/ntp_snippet.h"
 #include "components/ntp_snippets/ntp_snippets_fetcher.h"
+#include "components/ntp_snippets/ntp_snippets_scheduler.h"
 
 namespace ntp_snippets {
 
@@ -36,9 +37,12 @@ class NTPSnippetsService : public KeyedService, NTPSnippetsFetcher::Observer {
   // (British english person in the US) are not language code.
   NTPSnippetsService(scoped_refptr<base::SequencedTaskRunner> file_task_runner,
                      const std::string& application_language_code,
+                     NTPSnippetsScheduler* scheduler,
                      scoped_ptr<NTPSnippetsFetcher> snippets_fetcher);
   ~NTPSnippetsService() override;
 
+  void Init(bool enabled);
+
   // Fetches snippets from the server. |overwrite| is true if existing snippets
   // should be overwritten.
   void FetchSnippets(bool overwrite);
@@ -99,6 +103,9 @@ class NTPSnippetsService : public KeyedService, NTPSnippetsFetcher::Observer {
   // The observers.
   base::ObserverList<NTPSnippetsServiceObserver> observers_;
 
+  // Scheduler for fetching snippets. Not owned.
+  NTPSnippetsScheduler* scheduler_;
+
   // The snippets fetcher
   scoped_ptr<NTPSnippetsFetcher> snippets_fetcher_;
 
diff --git a/components/ntp_snippets/ntp_snippets_service_unittest.cc b/components/ntp_snippets/ntp_snippets_service_unittest.cc
index f801e94..c845b1b 100644
--- a/components/ntp_snippets/ntp_snippets_service_unittest.cc
+++ b/components/ntp_snippets/ntp_snippets_service_unittest.cc
@@ -61,7 +61,7 @@ class NTPSnippetsServiceTest : public testing::Test {
         signin_client_.get(), account_tracker_.get());
 
     scoped_ptr<NTPSnippetsService> service(
-        new NTPSnippetsService(task_runner.get(), std::string("fr"),
+        new NTPSnippetsService(task_runner.get(), std::string("fr"), nullptr,
           make_scoped_ptr(new NTPSnippetsFetcher(task_runner.get(),
             signin_manager, token_service, request_context_getter,
             base::FilePath()))));
@@ -75,7 +75,6 @@ class NTPSnippetsServiceTest : public testing::Test {
   DISALLOW_COPY_AND_ASSIGN(NTPSnippetsServiceTest);
 };
 
-
 TEST_F(NTPSnippetsServiceTest, Create) {
   scoped_ptr<NTPSnippetsService> service(CreateSnippetService());
   EXPECT_FALSE(service->is_loaded());
diff --git a/ios/chrome/browser/ntp_snippets/ios_chrome_ntp_snippets_service_factory.cc b/ios/chrome/browser/ntp_snippets/ios_chrome_ntp_snippets_service_factory.cc
index 0602d85..319d1f8 100644
--- a/ios/chrome/browser/ntp_snippets/ios_chrome_ntp_snippets_service_factory.cc
+++ b/ios/chrome/browser/ntp_snippets/ios_chrome_ntp_snippets_service_factory.cc
@@ -54,13 +54,15 @@ IOSChromeNTPSnippetsServiceFactory::BuildServiceInstanceFor(
   scoped_refptr<net::URLRequestContextGetter> request_context =
       browser_state->GetRequestContext();
 
+  ntp_snippets::NTPSnippetsScheduler* scheduler = nullptr;
+
   scoped_refptr<base::SequencedTaskRunner> task_runner =
       web::WebThread::GetBlockingPool()
           ->GetSequencedTaskRunnerWithShutdownBehavior(
               base::SequencedWorkerPool::GetSequenceToken(),
               base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN);
   return make_scoped_ptr(new ntp_snippets::NTPSnippetsService(
-      task_runner, GetApplicationContext()->GetApplicationLocale(),
+      task_runner, GetApplicationContext()->GetApplicationLocale(), scheduler,
       make_scoped_ptr(new ntp_snippets::NTPSnippetsFetcher(
           task_runner, (SigninManagerBase*)signin_manager, token_service,
           request_context, browser_state->GetStatePath()))));