Prepare for removal of source_filter.gypi:

runtime/platform/thread_macos.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_MACOS)
+
 #include "platform/thread.h"
 
-#include <sys/errno.h>
+#include <sys/errno.h>  // NOLINT
 
 #include "platform/assert.h"
 
 namespace dart {
 
 #define VALIDATE_PTHREAD_RESULT(result)         \
   if (result != 0) { \
     FATAL2("pthread error: %d (%s)", result, strerror(result)); \
   }
 
@@ skipping 234 matching lines @@
 }
 
 
 void Monitor::NotifyAll() {
   // TODO(iposva): Do we need to track lock owners?
   int result = pthread_cond_broadcast(data_.cond());
   VALIDATE_PTHREAD_RESULT(result);
 }
 
 }  // namespace dart
+
+#endif  // defined(TARGET_OS_MACOS)