Align base::hash_map with C++11.

base/debug/trace_event_impl.h

 // 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.
 
 
 #ifndef BASE_DEBUG_TRACE_EVENT_IMPL_H_
 #define BASE_DEBUG_TRACE_EVENT_IMPL_H_
 
 #include <stack>
 #include <string>
@@ skipping 27 matching lines @@
         name, reinterpret_cast<const void*>(id), extra)
 
 #define TRACE_EVENT_INSTANT_ETW(name, id, extra) \
     base::debug::TraceLog::AddTraceEventEtw( \
         TRACE_EVENT_PHASE_INSTANT, \
         name, reinterpret_cast<const void*>(id), extra)
 
 template <typename Type>
 struct DefaultSingletonTraits;
 
-#if defined(COMPILER_GCC)
-namespace BASE_HASH_NAMESPACE {
-template <>
-struct hash<base::MessageLoop*> {
-  std::size_t operator()(base::MessageLoop* value) const {
-    return reinterpret_cast<std::size_t>(value);
-  }
-};
-}  // BASE_HASH_NAMESPACE
-#endif
-
 namespace base {
 
 class WaitableEvent;
 class MessageLoop;
 
 namespace debug {
 
 // For any argument of type TRACE_VALUE_TYPE_CONVERTABLE the provided
 // class must implement this interface.
 class BASE_EXPORT ConvertableToTraceFormat
@@ skipping 743 matching lines @@
   scoped_refptr<MessageLoopProxy> flush_message_loop_proxy_;
   subtle::AtomicWord generation_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceLog);
 };
 
 }  // namespace debug
 }  // namespace base
 
 #endif  // BASE_DEBUG_TRACE_EVENT_IMPL_H_