Make original_response_headers parameter of NetworkDelegate::OnHeadersReceived const

chrome/browser/net/chrome_network_delegate.cc

Index: chrome/browser/net/chrome_network_delegate.cc
diff --git a/chrome/browser/net/chrome_network_delegate.cc b/chrome/browser/net/chrome_network_delegate.cc
index 828fe6665fb9348faaa06f9ad9780ee62a6c5ed2..f34396f5f34e6b33d0ed775d1ecec5572d5511d2 100644
--- a/chrome/browser/net/chrome_network_delegate.cc
+++ b/chrome/browser/net/chrome_network_delegate.cc
@@ -242,7 +242,7 @@ void ChromeNetworkDelegate::OnSendHeaders(
 int ChromeNetworkDelegate::OnHeadersReceived(
     net::URLRequest* request,
     const net::CompletionCallback& callback,
-    net::HttpResponseHeaders* original_response_headers,
+    const net::HttpResponseHeaders* original_response_headers,
     scoped_refptr<net::HttpResponseHeaders>* override_response_headers) {
   return ExtensionWebRequestEventRouter::GetInstance()->OnHeadersReceived(
       profile_, extension_info_map_.get(), request, callback,