Speed up sanitizing headers received from HTTP proxies.

net/http/http_response_headers.cc

 // Copyright (c) 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.
 
 // The rules for header parsing were borrowed from Firefox:
 // http://lxr.mozilla.org/seamonkey/source/netwerk/protocol/http/src/nsHttpResponseHead.cpp
 // The rules for parsing content-types were also borrowed from Firefox:
 // http://lxr.mozilla.org/mozilla/source/netwerk/base/src/nsURLHelper.cpp#834
 
 #include "net/http/http_response_headers.h"
@@ skipping 289 matching lines @@
   // Copy up to the null byte.  This just copies the status line.
   std::string new_raw_headers(raw_headers_.c_str());
   new_raw_headers.push_back('\0');
 
   std::string lowercase_name = base::ToLowerASCII(name);
   HeaderSet to_remove;
   to_remove.insert(lowercase_name);
   MergeWithHeaders(new_raw_headers, to_remove);
 }
 
+void HttpResponseHeaders::RemoveHeaders(
+    const std::unordered_set<std::string>& header_names) {
+  // Copy up to the null byte.  This just copies the status line.
+  std::string new_raw_headers(raw_headers_.c_str());
+  new_raw_headers.push_back('\0');
+
+  HeaderSet to_remove;
+  for (const auto& header_name : header_names) {
+    to_remove.insert(base::ToLowerASCII(header_name));
+  }
+  MergeWithHeaders(new_raw_headers, to_remove);
+}
+
 void HttpResponseHeaders::RemoveHeaderLine(const std::string& name,
                                            const std::string& value) {
   std::string name_lowercase = base::ToLowerASCII(name);
 
   std::string new_raw_headers(GetStatusLine());
   new_raw_headers.push_back('\0');
 
   new_raw_headers.reserve(raw_headers_.size());
 
   size_t iter = 0;
@@ skipping 1050 matching lines @@
   return true;
 }
 
 bool HttpResponseHeaders::IsChunkEncoded() const {
   // Ignore spurious chunked responses from HTTP/1.0 servers and proxies.
   return GetHttpVersion() >= HttpVersion(1, 1) &&
       HasHeaderValue("Transfer-Encoding", "chunked");
 }
 
 }  // namespace net