Use IOSImageDataFetcherWrapper for favicon

components/favicon/ios/web_favicon_driver.mm

 // Copyright 2015 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 "components/favicon/ios/web_favicon_driver.h"
 
 #include "base/bind.h"
+#include "base/memory/ptr_util.h"
 #include "components/favicon/core/favicon_url.h"
 #include "components/favicon/ios/favicon_url_util.h"
 #include "ios/web/public/browser_state.h"
 #include "ios/web/public/favicon_status.h"
 #include "ios/web/public/navigation_item.h"
 #include "ios/web/public/navigation_manager.h"
 #include "ios/web/public/web_state/web_state.h"
+#include "ios/web/public/web_thread.h"
+#include "net/url_request/url_fetcher.h"
+#include "skia/ext/skia_utils_ios.h"
+#include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/gfx/image/image.h"
 
 DEFINE_WEB_STATE_USER_DATA_KEY(favicon::WebFaviconDriver);
 
+// Callback for the download of favicon.
+using ImageDownloadCallback =
+    base::Callback<void(int image_id,
+                        int http_status_code,
+                        const GURL& image_url,
+                        const std::vector<SkBitmap>& bitmaps,
+                        const std::vector<gfx::Size>& sizes)>;
+
 namespace favicon {
 
 // static
 void WebFaviconDriver::CreateForWebState(
     web::WebState* web_state,
     FaviconService* favicon_service,
     history::HistoryService* history_service,
     bookmarks::BookmarkModel* bookmark_model) {
   if (FromWebState(web_state))
     return;
@@ skipping 19 matching lines @@
       web_state()->GetNavigationManager()->GetLastCommittedItem();
   return item ? item->GetFavicon().valid : false;
 }
 
 int WebFaviconDriver::StartDownload(const GURL& url, int max_image_size) {
   if (WasUnableToDownloadFavicon(url)) {
     DVLOG(1) << "Skip Failed FavIcon: " << url;
     return 0;
   }
 
-  return web_state()->DownloadImage(
-      url, true, max_image_size, false,
-      base::Bind(&FaviconDriverImpl::DidDownloadFavicon,
-                 base::Unretained(this)));
+  static int downloaded_image_count = 0;
+  int local_download_id = ++downloaded_image_count;
+
+  ImageDownloadCallback local_image_callback = base::Bind(
+      &FaviconDriverImpl::DidDownloadFavicon, base::Unretained(this));
+  GURL local_url(url);
+
+  image_fetcher::IOSImageDataFetcherCallback local_callback =
+      ^(NSData* data, const int response_code) {
+        std::vector<SkBitmap> frames;
+        std::vector<gfx::Size> sizes;
+        if (data) {

[sdefresne, 2017/02/06 17:33:33]

Why convert data to std::vector<SkBitmap> to just discard them if response_code
is invalid. I would suggest instead to first check the response_code, and only
decode data if valid.

  if (response_code == net::URLFetcher::RESPONSE_CODE_INVALID)
    return;

  std::vector<SkBitmap> frames;
  std::vector<gfx::Size> sizes;
  ...

[gambard, 2017/02/07 10:03:33]

Done.

+          frames = skia::ImageDataToSkBitmaps(data);
+          for (const auto& frame : frames) {
+            sizes.push_back(gfx::Size(frame.width(), frame.height()));
+          }
+        }
+        if (response_code != net::URLFetcher::RESPONSE_CODE_INVALID) {

[mef, 2017/02/06 16:36:17]

Is this the only reference from net/url_request/url_fetcher.h here?
Could it make sense to pass explicit flag and don't depend on net?

[gambard, 2017/02/07 10:03:33]

Done.

+          local_image_callback.Run(local_download_id, response_code, local_url,
+                                   frames, sizes);
+        }
+      };
+  image_fetcher_.FetchImageDataWebpDecoded(url, local_callback);
+
+  return downloaded_image_count;
 }
 
 bool WebFaviconDriver::IsOffTheRecord() {
   DCHECK(web_state());
   return web_state()->GetBrowserState()->IsOffTheRecord();
 }
 
 GURL WebFaviconDriver::GetActiveURL() {
   web::NavigationItem* item =
       web_state()->GetNavigationManager()->GetVisibleItem();
@@ skipping 17 matching lines @@
 
   NotifyFaviconUpdatedObservers(notification_icon_type, icon_url,
                                 icon_url_changed, image);
 }
 
 WebFaviconDriver::WebFaviconDriver(web::WebState* web_state,
                                    FaviconService* favicon_service,
                                    history::HistoryService* history_service,
                                    bookmarks::BookmarkModel* bookmark_model)
     : web::WebStateObserver(web_state),
-      FaviconDriverImpl(favicon_service, history_service, bookmark_model) {
-}
+      FaviconDriverImpl(favicon_service, history_service, bookmark_model),
+      image_fetcher_(web_state->GetBrowserState()->GetRequestContext(),
+                     web::WebThread::GetBlockingPool()) {}
 
 WebFaviconDriver::~WebFaviconDriver() {
 }
 
 void WebFaviconDriver::FaviconUrlUpdated(
     const std::vector<web::FaviconURL>& candidates) {
   DCHECK(!candidates.empty());
   OnUpdateFaviconURL(GetActiveURL(), FaviconURLsFromWebFaviconURLs(candidates));
 }
 
 }  // namespace favicon