Make message_names.cc build 10-30x faster.

tools/ipc_fuzzer/message_lib/message_names.h

 // Copyright 2013 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.
 
 #ifndef TOOLS_IPC_FUZZER_MESSAGE_LIB_MESSAGE_NAMES_H_
 #define TOOLS_IPC_FUZZER_MESSAGE_LIB_MESSAGE_NAMES_H_
 
 #include <stdint.h>
 
-#include <map>
 #include <string>
+#include <unordered_map>
 #include "base/logging.h"
 #include "base/macros.h"
 
 namespace ipc_fuzzer {
 
 class MessageNames {
  public:
   MessageNames();
   ~MessageNames();
   static MessageNames* GetInstance();
@@ skipping 17 matching lines @@
     return it->second;
   }
 
   uint32_t NameToType(const std::string& name) {
     NameToTypeMap::iterator it = type_map_.find(name);
     CHECK(it != type_map_.end());
     return it->second;
   }
 
  private:
-  typedef std::map<uint32_t, std::string> TypeToNameMap;
-  typedef std::map<std::string, uint32_t> NameToTypeMap;
+  typedef std::unordered_map<uint32_t, std::string> TypeToNameMap;
+  typedef std::unordered_map<std::string, uint32_t> NameToTypeMap;
   TypeToNameMap name_map_;
   NameToTypeMap type_map_;
 
   static MessageNames* all_names_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageNames);
 };
 
 }  // namespace ipc_fuzzer
 
 #endif  // TOOLS_IPC_FUZZER_MESSAGE_LIB_MESSAGE_NAMES_H_