Mojo: Move public C system header files to mojo/public/c/system/.

mojo/public/utility/thread.h

 // Copyright 2014 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.
 
 #ifndef MOJO_PUBLIC_UTILITY_THREAD_H_
 #define MOJO_PUBLIC_UTILITY_THREAD_H_
 
 #ifdef _WIN32
 #error "Not implemented: See crbug.com/342893."
 #endif
 
 #include <pthread.h>
 #include <stddef.h>
 
-#include "mojo/public/system/macros.h"
+#include "mojo/public/c/system/macros.h"
 
 namespace mojo {
 
 // This class is thread-friendly, not thread-safe (e.g., you mustn't call
 // |Join()| from multiple threads and/or simultaneously try to destroy the
 // object).
 class Thread {
  public:
   // TODO(vtl): Support non-joinable? priority?
   class Options {
@@ skipping 27 matching lines @@
   pthread_t thread_;
   bool started_;
   bool joined_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(Thread);
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_UTILITY_THREAD_H_