Remove unnecessary includes of v8 headers from platform files

src/platform-posix.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 48 matching lines @@
 
 #undef MAP_TYPE
 
 #if defined(ANDROID) && !defined(V8_ANDROID_LOG_STDOUT)
 #define LOG_TAG "v8"
 #include <android/log.h>
 #endif
 
 #include "v8.h"
 
-#include "codegen.h"
 #include "isolate-inl.h"
 #include "platform.h"
 
 namespace v8 {
 namespace internal {
 
 // 0 is never a valid thread id.
 static const pthread_t kNoThread = (pthread_t) 0;
 
 
@@ skipping 732 matching lines @@
 
 void Thread::SetThreadLocal(LocalStorageKey key, void* value) {
   pthread_key_t pthread_key = LocalKeyToPthreadKey(key);
   int result = pthread_setspecific(pthread_key, value);
   ASSERT_EQ(0, result);
   USE(result);
 }
 
 
 } }  // namespace v8::internal