Make header include guards great again

runtime/bin/directory.h

Index: runtime/bin/directory.h
diff --git a/runtime/bin/directory.h b/runtime/bin/directory.h
index ee1f389cfe47f0f32b149d26372eb2caf39bde38..a15e6ad2bc6a1fd21bdec90dec6b68999007a190 100644
--- a/runtime/bin/directory.h
+++ b/runtime/bin/directory.h
@@ -2,8 +2,8 @@
 // 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_DIRECTORY_H_
-#define BIN_DIRECTORY_H_
+#ifndef RUNTIME_BIN_DIRECTORY_H_
+#define RUNTIME_BIN_DIRECTORY_H_
 
 #include "bin/builtin.h"
 #include "bin/dartutils.h"
@@ -300,4 +300,4 @@ class Directory {
 }  // namespace bin
 }  // namespace dart
 
-#endif  // BIN_DIRECTORY_H_
+#endif  // RUNTIME_BIN_DIRECTORY_H_