Make header include guards great again

runtime/bin/extensions.h

 // 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.
 
-#ifndef BIN_EXTENSIONS_H_
-#define BIN_EXTENSIONS_H_
+#ifndef RUNTIME_BIN_EXTENSIONS_H_
+#define RUNTIME_BIN_EXTENSIONS_H_
 
 #include "include/dart_api.h"
 #include "platform/globals.h"
 
 namespace dart {
 namespace bin {
 
 class Extensions {
  public:
   // TODO(whesse): Make extension load from a relative path relative to
@@ skipping 17 matching lines @@
   // The returned string is scope allocated.
   static const char* Concatenate(const char** strings);
 
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(Extensions);
 };
 
 }  // namespace bin
 }  // namespace dart
 
-#endif  // BIN_EXTENSIONS_H_
+#endif  // RUNTIME_BIN_EXTENSIONS_H_