Rename TARGET_OS_* to HOST_OS_*.

runtime/bin/file_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/file.h"
 
 #include <fcntl.h>     // NOLINT
 #include <io.h>        // NOLINT
 #include <stdio.h>     // NOLINT
 #include <string.h>    // NOLINT
 #include <sys/stat.h>  // NOLINT
 #include <sys/utime.h>  // NOLINT
 #include <WinIoCtl.h>  // NOLINT
@@ skipping 807 matching lines @@
       (file_info[0].nFileIndexLow == file_info[1].nFileIndexLow)) {
     return kIdentical;
   } else {
     return kDifferent;
   }
 }
 
 }  // namespace bin
 }  // namespace dart
 
-#endif  // defined(TARGET_OS_WINDOWS)
+#endif  // defined(HOST_OS_WINDOWS)