Change net::LOAD_MAIN_FRAME to net::LOAD_MAIN_FRAME_DEPRECATED to discourage

ios/chrome/browser/net/ios_chrome_network_delegate.cc

 // 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 "ios/chrome/browser/net/ios_chrome_network_delegate.h"
 
 #include <stdlib.h>
 
 #include "base/base_paths.h"
 #include "base/debug/alias.h"
@@ skipping 38 matching lines @@
   NOTREACHED();
 }
 
 // Record network errors that HTTP requests complete with, including OK and
 // ABORTED.
 void RecordNetworkErrorHistograms(const net::URLRequest* request) {
   if (request->url().SchemeIs("http")) {
     UMA_HISTOGRAM_SPARSE_SLOWLY("Net.HttpRequestCompletionErrorCodes",
                                 std::abs(request->status().error()));
 
-    if (request->load_flags() & net::LOAD_MAIN_FRAME) {
+    if (request->load_flags() & net::LOAD_MAIN_FRAME_DEPRECATED) {
       UMA_HISTOGRAM_SPARSE_SLOWLY(
           "Net.HttpRequestCompletionErrorCodes.MainFrame",
           std::abs(request->status().error()));
     }
   }
 }
 
 }  // namespace
 
 IOSChromeNetworkDelegate::IOSChromeNetworkDelegate()
@@ skipping 96 matching lines @@
 }
 
 bool IOSChromeNetworkDelegate::
     OnCancelURLRequestWithPolicyViolatingReferrerHeader(
         const net::URLRequest& request,
         const GURL& target_url,
         const GURL& referrer_url) const {
   ReportInvalidReferrerSend(target_url, referrer_url);
   return true;
 }