Adjust URLFetcher::Create API so that object is returned as scoped_ptr.

ios/chrome/browser/net/retryable_url_fetcher.mm

 // 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.
 
 #import "ios/chrome/browser/net/retryable_url_fetcher.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/sys_string_conversions.h"
 #include "net/http/http_status_code.h"
@@ skipping 40 matching lines @@
       backoffEntry_.reset(new net::BackoffEntry(policy));
   }
   return self;
 }
 
 - (void)startFetch {
   DCHECK(requestContextGetter_.get());
   GURL url(base::SysNSStringToUTF8([delegate_ urlToFetch]));
   if (url.is_valid()) {
     fetcherDelegate_.reset(new URLRequestDelegate(self));
-    fetcher_.reset(net::URLFetcher::Create(url, net::URLFetcher::GET,
-                                           fetcherDelegate_.get()));
+    fetcher_ = net::URLFetcher::Create(url, net::URLFetcher::GET,
+                                       fetcherDelegate_.get());
     fetcher_->SetRequestContext(requestContextGetter_.get());
     fetcher_->Start();
   }
 }
 
 - (int)failureCount {
   return backoffEntry_ ? backoffEntry_->failure_count() : 0;
 }
 
 - (void)urlFetchDidComplete:(const net::URLFetcher*)fetcher {
@@ skipping 10 matching lines @@
   NSString* response = nil;
   if (success) {
     std::string responseString;
     if (fetcher->GetResponseAsString(&responseString))
       response = base::SysUTF8ToNSString(responseString);
   }
   [delegate_ processSuccessResponse:response];
 }
 
 @end