Implement server-suggested update check backoff

chrome/browser/android/webapk/webapk_installer.h

 // 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_WEBAPK_WEBAPK_INSTALLER_H_
 #define CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_INSTALLER_H_
 
 #include <jni.h>
 #include <map>
 #include <memory>
@@ skipping 25 matching lines @@
 
 // Talks to Chrome WebAPK server and Google Play to generate a WebAPK on the
 // server, download it, and install it. The native WebApkInstaller owns the
 // Java WebApkInstaller counterpart.
 class WebApkInstaller : public net::URLFetcherDelegate {
  public:
   // Called when the creation/updating of a WebAPK is finished or failed.
   // Parameters:
   // - whether the process succeeds.
   // - the package name of the WebAPK.
-  using FinishCallback = base::Callback<void(bool, const std::string&)>;
+  // - true if Chrome received a "request updates less frequently" directive
+  //   from the WebAPK server.
+  using FinishCallback = base::Callback<void(bool, bool, const std::string&)>;
 
   ~WebApkInstaller() override;
 
   // Creates a self-owned WebApkInstaller instance and talks to the Chrome
   // WebAPK server to generate a WebAPK on the server and to Google Play to
   // install the downloaded WebAPK. Calls |callback| once the install completed
   // or failed.
   static void InstallAsync(content::BrowserContext* context,
                            const ShortcutInfo& shortcut_info,
                            const SkBitmap& shortcut_icon,
@@ skipping 206 matching lines @@
   // The number of milliseconds to wait for the WebAPK download URL from the
   // WebAPK server.
   int webapk_download_url_timeout_ms_;
 
   // The number of milliseconds to wait for the WebAPK download to complete.
   int download_timeout_ms_;
 
   // WebAPK package name.
   std::string webapk_package_;
 
+  // Whether the server wants the WebAPK to request updates less frequently.
+  bool relax_updates_;
+
   // WebAPK version code.
   int webapk_version_;
 
   // Indicates whether the installer is for installing or updating a WebAPK.
   TaskType task_type_;
 
   // Points to the Java Object.
   base::android::ScopedJavaGlobalRef<jobject> java_ref_;
 
   // Used to get |weak_ptr_|.
   base::WeakPtrFactory<WebApkInstaller> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebApkInstaller);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_INSTALLER_H_