Rename TARGET_OS_* to HOST_OS_*.

runtime/bin/platform_win.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
-#if defined(TARGET_OS_WINDOWS)
+#if defined(HOST_OS_WINDOWS)
 
 #include "bin/platform.h"
 
 #include <crtdbg.h>
 
 #include "bin/file.h"
 #include "bin/lockers.h"
 #include "bin/log.h"
 #if !defined(DART_IO_DISABLED) && !defined(PLATFORM_DISABLE_SOCKET)
 #include "bin/socket.h"
@@ skipping 270 matching lines @@
   // Restore the console's output code page
   PlatformWin::RestoreConsole();
   // On Windows we use ExitProcess so that threads can't clobber the exit_code.
   // See: https://code.google.com/p/nativeclient/issues/detail?id=2870
   ::ExitProcess(exit_code);
 }
 
 }  // namespace bin
 }  // namespace dart
 
-#endif  // defined(TARGET_OS_WINDOWS)
+#endif  // defined(HOST_OS_WINDOWS)