Reland "Enable libc++ on Android"

base/containers/hash_tables.h

 // 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.
 //
 
 //
 // Deal with the differences between Microsoft and GNU implemenations
 // of hash_map. Allows all platforms to use |base::hash_map| and
 // |base::hash_set|.
 //  eg:
@@ skipping 27 matching lines @@
 #define BASE_HASH_NAMESPACE base_hash
 
 // This is a hack to disable the gcc 4.4 warning about hash_map and hash_set
 // being deprecated.  We can get rid of this when we upgrade to VS2008 and we
 // can use <tr1/unordered_map> and <tr1/unordered_set>.
 #ifdef __DEPRECATED
 #define CHROME_OLD__DEPRECATED __DEPRECATED
 #undef __DEPRECATED
 #endif
 
-#if defined(OS_ANDROID)
-#include <hash_map>
-#include <hash_set>
-#define BASE_HASH_IMPL_NAMESPACE std
-#else
 #include <ext/hash_map>
 #include <ext/hash_set>
 #define BASE_HASH_IMPL_NAMESPACE __gnu_cxx
-#endif
 
 #include <string>
 
 #ifdef CHROME_OLD__DEPRECATED
 #define __DEPRECATED CHROME_OLD__DEPRECATED
 #undef CHROME_OLD__DEPRECATED
 #endif
 
 namespace BASE_HASH_NAMESPACE {
 
@@ skipping 10 matching lines @@
 };
 
 template<typename T>
 struct hash<T*> {
   std::size_t operator()(T* value) const {
     return BASE_HASH_IMPL_NAMESPACE::hash<uintptr_t>()(
         reinterpret_cast<uintptr_t>(value));
   }
 };
 
-#if !defined(OS_ANDROID)
 // The GNU C++ library provides identity hash functions for many integral types,
 // but not for |long long|.  This hash function will truncate if |size_t| is
 // narrower than |long long|.  This is probably good enough for what we will
 // use it for.
 
 #define DEFINE_TRIVIAL_HASH(integral_type) \
     template<> \
     struct hash<integral_type> { \
       std::size_t operator()(integral_type value) const { \
         return static_cast<std::size_t>(value); \
       } \
     }
 
 DEFINE_TRIVIAL_HASH(long long);
 DEFINE_TRIVIAL_HASH(unsigned long long);
 
 #undef DEFINE_TRIVIAL_HASH
-#endif  // !defined(OS_ANDROID)
 
 // Implement string hash functions so that strings of various flavors can
 // be used as keys in STL maps and sets.  The hash algorithm comes from the
 // GNU C++ library, in <tr1/functional>.  It is duplicated here because GCC
 // versions prior to 4.3.2 are unable to compile <tr1/functional> when RTTI
 // is disabled, as it is in our build.
 
 #define DEFINE_STRING_HASH(string_type) \
     template<> \
     struct hash<string_type> { \
@@ skipping 203 matching lines @@
     return base::HashPair(value.first, value.second);
   }
 };
 
 }  // namespace BASE_HASH_NAMESPACE
 
 #undef DEFINE_PAIR_HASH_FUNCTION_START
 #undef DEFINE_PAIR_HASH_FUNCTION_END
 
 #endif  // BASE_CONTAINERS_HASH_TABLES_H_