[Offline pages] Implementation of OfflineBackgroundTask using background_task_scheduler

chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflineBackgroundTask.java

Index: chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflineBackgroundTask.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflineBackgroundTask.java b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflineBackgroundTask.java
new file mode 100644
index 0000000000000000000000000000000000000000..4a1c67d7d38aea60bad3bbcc11eb9eb46097b19c
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflineBackgroundTask.java
@@ -0,0 +1,48 @@
+// 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.chrome.browser.offlinepages;
+
+import android.content.Context;
+
+import org.chromium.base.Callback;
+import org.chromium.chrome.browser.offlinepages.interfaces.BackgroundSchedulerProcessor;
+import org.chromium.components.background_task_scheduler.BackgroundTask;
+import org.chromium.components.background_task_scheduler.BackgroundTask.TaskFinishedCallback;
+import org.chromium.components.background_task_scheduler.TaskIds;
+import org.chromium.components.background_task_scheduler.TaskParameters;
+
+/**
+ * Handles servicing background offlining requests coming via background_task_scheduler component.
+ */
+public class OfflineBackgroundTask implements BackgroundTask {
+    BackgroundSchedulerProcessor mBackgroundProcessor;
+
+    public OfflineBackgroundTask() {
+        mBackgroundProcessor = new BackgroundSchedulerProcessorImpl();
+    }
+
+    @Override
+    public boolean onStartTask(
+            Context context, TaskParameters taskParameters, TaskFinishedCallback callback) {
+        assert taskParameters.getTaskId() == TaskIds.OFFLINE_PAGES_BACKGROUND_JOB_ID;
+        return BackgroundOfflinerTask.startBackgroundRequestsImpl(
+                mBackgroundProcessor, context, taskParameters.getExtras(), wrapCallback(callback));
+    }
+
+    @Override
+    public boolean onStopTask(Context context, TaskParameters taskParameters) {
+        return mBackgroundProcessor.stopScheduledProcessing();
+    }
+
+    /** Wraps the callback for code reuse */
+    private Callback<Boolean> wrapCallback(final TaskFinishedCallback callback) {
+        return new Callback<Boolean>() {
+            @Override
+            public void onResult(Boolean result) {
+                callback.taskFinished(result);
+            }
+        };
+    }
+}