Add possibility to define data callback to BitmapFetcher

chrome/browser/bitmap_fetcher/bitmap_fetcher.h

 // Copyright 2014 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_BITMAP_FETCHER_BITMAP_FETCHER_H_
 #define CHROME_BROWSER_BITMAP_FETCHER_BITMAP_FETCHER_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/bitmap_fetcher/bitmap_fetcher_delegate.h"
 #include "chrome/browser/image_decoder.h"
@@ skipping 11 matching lines @@
 
 // Asynchrounously fetches an image from the given URL and returns the
 // decoded Bitmap to the provided BitmapFetcherDelegate.
 class BitmapFetcher : public net::URLFetcherDelegate,
                       public ImageDecoder::ImageRequest {
  public:
   BitmapFetcher(const GURL& url, BitmapFetcherDelegate* delegate);
   ~BitmapFetcher() override;
 
   const GURL& url() const { return url_; }
+  net::URLFetcher* url_fetcher() { return url_fetcher_.get(); }
 
   // Start fetching the URL with the fetcher. The delegate is notified

[Peter Kasting, 2015/04/24 23:18:21]

This comment needs updating.  In particular you should motivate why Init()
doesn't automatically Start().

   // asynchronously when done.  Start may be called more than once in some
   // cases.  If so, subsequent starts will be ignored since the operation is
   // already in progress.  Arguments are used to configure the internal fetcher.
   // Values for |load_flags| are defined in net/base/load_flags.h.  In general,
   // |net::LOAD_NORMAL| is appropriate.
-  void Start(net::URLRequestContextGetter* request_context,
-             const std::string& referrer,
-             net::URLRequest::ReferrerPolicy referrer_policy,
-             int load_flags);
+  void Init(net::URLRequestContextGetter* request_context,
+            const std::string& referrer,
+            net::URLRequest::ReferrerPolicy referrer_policy,
+            int load_flags);
+
+  void Start();

[Peter Kasting, 2015/04/24 23:18:21]

You should add a comment here.

 
   // Methods inherited from URLFetcherDelegate
 
   // This will be called when the URL has been fetched, successfully or not.
   // Use accessor methods on |source| to get the results.
   void OnURLFetchComplete(const net::URLFetcher* source) override;
 
   // This will be called when some part of the response is read. |current|
   // denotes the number of bytes received up to the call, and |total| is the
   // expected total size of the response (or -1 if not determined).
@@ skipping 18 matching lines @@
   scoped_ptr<net::URLFetcher> url_fetcher_;
   const GURL url_;
   BitmapFetcherDelegate* const delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(BitmapFetcher);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_BITMAP_FETCHER_BITMAP_FETCHER_H_