Clean up Android DownloadManager code as most download now go through Chrome Network stack

chrome/browser/android/download/download_controller.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.
 
 // This class pairs with DownloadController on Java side to forward requests
 // for GET downloads to the current DownloadListener. POST downloads are
 // handled on the native side.
 //
 // Both classes are Singleton classes. C++ object owns Java object.
 //
@@ skipping 58 matching lines @@
  private:
   struct JavaObject;
   friend struct base::DefaultSingletonTraits<DownloadController>;
   DownloadController();
   ~DownloadController() override;
 
   // Helper method for implementing AcquireFileAccessPermission().
   bool HasFileAccessPermission(ui::WindowAndroid* window_android);
 
   // DownloadControllerBase implementation.
-  void CreateGETDownload(
-      const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
-      bool must_download,
-      const DownloadInfo& info) override;
   void OnDownloadStarted(content::DownloadItem* download_item) override;
   void StartContextMenuDownload(const content::ContextMenuParams& params,
                                 content::WebContents* web_contents,
                                 bool is_link,
                                 const std::string& extra_headers) override;
   void DangerousDownloadValidated(content::WebContents* web_contents,
                                   const std::string& download_guid,
                                   bool accept) override;
 
   // DownloadItem::Observer interface.
   void OnDownloadUpdated(content::DownloadItem* item) override;
 
-  void StartAndroidDownload(
-      const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
-      bool must_download,
-      const DownloadInfo& info);
-  void StartAndroidDownloadInternal(
-      const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
-      bool must_download,
-      const DownloadInfo& info,
-      bool allowed);
-
   // The download item contains dangerous file types.
   void OnDangerousDownload(content::DownloadItem *item);
 
   base::android::ScopedJavaLocalRef<jobject> GetContentViewCoreFromWebContents(
       content::WebContents* web_contents);
 
   // Creates Java object if it is not created already and returns it.
   JavaObject* GetJavaObject();
 
   JavaObject* java_object_;
 
   std::string default_file_name_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadController);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_DOWNLOAD_DOWNLOAD_CONTROLLER_H_