Remove the old image fetcher

ios/chrome/browser/net/image_fetcher.h

-// Copyright 2011 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 IOS_CHROME_BROWSER_NET_IMAGE_FETCHER_H_
-#define IOS_CHROME_BROWSER_NET_IMAGE_FETCHER_H_
-
-#include <map>
-
-#include "base/mac/scoped_block.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/weak_ptr.h"
-#include "net/url_request/url_fetcher_delegate.h"
-#include "net/url_request/url_request.h"
-
-class GURL;
-@class NSData;
-
-namespace base {
-class TaskRunner;
-}
-
-namespace net {
-class URLRequestContextGetter;
-}
-
-// Callback that informs of the download of an image encoded in |data|,
-// downloaded from |url|, and with the http status |http_response_code|. If the
-// url is a data URL, |http_response_code| is always 200.
-using ImageFetchedCallback =
-    void (^)(const GURL& url, int http_response_code, NSData* data);
-
-// Utility class that will retrieve an image from an URL. The image is returned
-// as NSData which can be used with +[UIImage imageWithData:]. This class
-// usually returns the raw bytes retrieved from the network without any
-// processing, with the exception of WebP encoded images. Those are decoded and
-// then reencoded in a format suitable for UIImage.
-// An instance of this class can download a number of images at the same time.
-class ImageFetcher : public net::URLFetcherDelegate {
- public:
-  // The TaskRunner is used to eventually decode the image.
-  explicit ImageFetcher(const scoped_refptr<base::TaskRunner>& task_runner);
-  ~ImageFetcher() override;
-
-  // Start downloading the image at the given |url|. The |callback| will be
-  // called with the downloaded image, or nil if any error happened. The
-  // |referrer| and |referrer_policy| will be passed on to the underlying
-  // URLFetcher.
-  // This method assumes the request context getter has been set.
-  // (virtual for testing)
-  virtual void StartDownload(const GURL& url,
-                             ImageFetchedCallback callback,
-                             const std::string& referrer,
-                             net::URLRequest::ReferrerPolicy referrer_policy);
-
-  // Helper method to call StartDownload without a referrer.
-  // (virtual for testing)
-  virtual void StartDownload(const GURL& url, ImageFetchedCallback callback);
-
-  // A valid request context getter is required before starting the download.
-  // (virtual for testing)
-  virtual void SetRequestContextGetter(const scoped_refptr<
-      net::URLRequestContextGetter>& request_context_getter);
-
-  // net::URLFetcherDelegate:
-  void OnURLFetchComplete(const net::URLFetcher* source) override;
-
- private:
-  // Runs the callback with the given arguments.
-  void RunCallback(const base::mac::ScopedBlock<ImageFetchedCallback>& callback,
-                   const GURL& url,
-                   const int http_response_code,
-                   NSData* data);
-
-  // Tracks open download requests.  The key is the URLFetcher object doing the
-  // fetch; the value is the callback to use when the download request
-  // completes. When a download request completes, the URLFetcher must be
-  // deleted and the callback called and released.
-  std::map<const net::URLFetcher*, ImageFetchedCallback> downloads_in_progress_;
-  scoped_refptr<net::URLRequestContextGetter> request_context_getter_;
-
-  // The task runner used to decode images if necessary.
-  const scoped_refptr<base::TaskRunner> task_runner_;
-
-  // The WeakPtrFactory is used to cancel callbacks if ImageFetcher is destroyed
-  // during WebP decoding.
-  base::WeakPtrFactory<ImageFetcher> weak_factory_;
-};
-
-#endif  // IOS_CHROME_BROWSER_NET_IMAGE_FETCHER_H_