Implement DownloadImage directly in WebStateImpl

ios/web/public/web_state/ui/crw_web_delegate.h

 // Copyright 2012 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_WEB_PUBLIC_WEB_STATE_UI_CRW_WEB_DELEGATE_H_
 #define IOS_WEB_PUBLIC_WEB_STATE_UI_CRW_WEB_DELEGATE_H_
 
 #include <stdint.h>
 #import <UIKit/UIKit.h>
 #include <vector>
@@ skipping 91 matching lines @@
 // Consults the delegate whether a form should be resubmitted for a request.
 // Occurs when a POST request is reached when navigating through history.
 // Call |continueBlock| if a form should be resubmitted.
 // Call |cancelBlock| if a form should not be resubmitted.
 // Delegates must call either of these (just once) before the load will
 // continue.
 - (void)webController:(CRWWebController*)webController
     onFormResubmissionForRequest:(NSURLRequest*)request
                    continueBlock:(ProceduralBlock)continueBlock
                      cancelBlock:(ProceduralBlock)cancelBlock;
-// Returns the unique id of the download request and starts downloading the
-// image at |url| without sending the cookies. Invokes |callback| on completion.
-- (int)downloadImageAtUrl:(const GURL&)url
-    maxBitmapSize:(uint32_t)maxBitmapSize
-         callback:(const web::WebState::ImageDownloadCallback&)callback;
 
 // ---------------------------------------------------------------------
 // TODO(rohitrao): Eliminate as many of the following delegate methods as
 // possible.  They only exist because the Tab and CRWWebController logic was
 // very intertwined. We should streamline the logic to jump between classes
 // less, then remove any delegate method that becomes unneccessary as a result.
 
 // Called when the page is reloaded.
 - (void)webWillReload;
 // Called when a page is loaded using loadWithParams.  In
@@ skipping 82 matching lines @@
 // Called when a PassKit file is downloaded. |data| should be the data from a
 // PassKit file, but this is not guaranteed, and the delegate is responsible for
 // error handling non PassKit data using -[PKPass initWithData:error:]. If the
 // download does not successfully complete, |data| will be nil.
 - (void)webController:(CRWWebController*)webController
     didLoadPassKitObject:(NSData*)data;
 
 @end
 
 #endif  // IOS_WEB_PUBLIC_WEB_STATE_UI_CRW_WEB_DELEGATE_H_