[Offline Prefetch] Create a new JobScheduler task to wake up for net activity.

chrome/browser/android/offline_pages/prefetch/prefetch_background_task.cc

+// 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.
+
+#include "chrome/browser/android/offline_pages/prefetch/prefetch_background_task.h"
+
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/profiles/profile_android.h"
+#include "components/offline_pages/content/prefetch_service_factory.h"
+#include "content/public/browser/browser_context.h"
+#include "jni/PrefetchBackgroundTask_jni.h"
+
+using base::android::JavaParamRef;
+using base::android::ScopedJavaGlobalRef;
+using base::android::ScopedJavaLocalRef;
+
+namespace offline_pages {
+namespace prefetch {
+
+// JNI call to start request processing in scheduled mode.
+static jboolean StartPrefetchTask(JNIEnv* env,
+                                  const JavaParamRef<jobject>& jcaller,
+                                  const JavaParamRef<jobject>& jprofile) {
+  Profile* profile = ProfileAndroid::FromProfileAndroid(jprofile);
+  DCHECK(profile);
+
+  PrefetchService* prefetch_service =
+      PrefetchServiceFactory::GetForBrowserContext(profile);
+  if (!prefetch_service)
+    return false;
+
+  prefetch_service->BeginBackgroundTask(
+      base::MakeUnique<PrefetchBackgroundTask>(env, jcaller, prefetch_service));
+  return true;
+}
+
+}  // namespace prefetch
+
+// static
+void PrefetchBackgroundTask::Schedule() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  return prefetch::Java_PrefetchBackgroundTask_scheduleTask(env);
+}
+
+// static
+void PrefetchBackgroundTask::Cancel() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  return prefetch::Java_PrefetchBackgroundTask_cancelTask(env);
+}
+
+PrefetchBackgroundTask::PrefetchBackgroundTask(
+    JNIEnv* env,
+    const JavaParamRef<jobject>& java_prefetch_background_task,
+    PrefetchService* service)
+    : java_prefetch_background_task_(java_prefetch_background_task),
+      service_(service) {
+  // Give the Java side a pointer to the new background task object.
+  prefetch::Java_PrefetchBackgroundTask_setNativeTask(
+      env, java_prefetch_background_task_, reinterpret_cast<jlong>(this));
+}
+
+PrefetchBackgroundTask::~PrefetchBackgroundTask() {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  prefetch::Java_PrefetchBackgroundTask_doneProcessing(
+      env, java_prefetch_background_task_.obj(), needs_reschedule_);
+}
+
+bool PrefetchBackgroundTask::OnStopTask(JNIEnv* env,
+                                        const JavaParamRef<jobject>& jcaller) {
+  DCHECK(jcaller.obj() == java_prefetch_background_task_.obj());
+  service_->StopBackgroundTask(this);
+  return needs_reschedule_;
+}
+
+void PrefetchBackgroundTask::SetNeedsReschedule(bool reschedule) {
+  needs_reschedule_ = reschedule;
+}
+
+bool RegisterPrefetchBackgroundTask(JNIEnv* env) {
+  return prefetch::RegisterNativesImpl(env);
+}
+
+}  // namespace offline_pages