Do not override User-Agent header added by WebCore

webkit/glue/weburlloader_impl.cc

 // Copyright (c) 2011 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.
 
 // An implementation of WebURLLoader in terms of ResourceLoaderBridge.
 
 #include "webkit/glue/weburlloader_impl.h"
 
 #include "base/file_path.h"
 #include "base/message_loop.h"
@@ skipping 51 matching lines @@
         has_accept_header_(false) {
   }
 
   virtual void visitHeader(const WebString& name, const WebString& value) {
     // TODO(darin): is UTF-8 really correct here?  It is if the strings are
     // already ASCII (i.e., if they are already escaped properly).
     const std::string& name_utf8 = name.utf8();
     const std::string& value_utf8 = value.utf8();
 
     // Skip over referrer headers found in the header map because we already
-    // pulled it out as a separate parameter.  We likewise prune the UA since
-    // that will be added back by the network layer.
-    if (LowerCaseEqualsASCII(name_utf8, "referer") ||
-        LowerCaseEqualsASCII(name_utf8, "user-agent"))
+    // pulled it out as a separate parameter.
+    if (LowerCaseEqualsASCII(name_utf8, "referer"))
       return;
 
     // Skip over "Cache-Control: max-age=0" header if the corresponding
     // load flag is already specified. FrameLoader sets both the flag and
     // the extra header -- the extra header is redundant since our network
     // implementation will add the necessary headers based on load flags.
     // See http://code.google.com/p/chromium/issues/detail?id=3434.
     if ((load_flags_ & net::LOAD_VALIDATE_CACHE) &&
         LowerCaseEqualsASCII(name_utf8, "cache-control") &&
         LowerCaseEqualsASCII(value_utf8, "max-age=0"))
@@ skipping 666 matching lines @@
 
 void WebURLLoaderImpl::cancel() {
   context_->Cancel();
 }
 
 void WebURLLoaderImpl::setDefersLoading(bool value) {
   context_->SetDefersLoading(value);
 }
 
 }  // namespace webkit_glue