Make header include guards great again

runtime/bin/file_system_watcher.h

Index: runtime/bin/file_system_watcher.h
diff --git a/runtime/bin/file_system_watcher.h b/runtime/bin/file_system_watcher.h
index 5026da71e38ef044ca188c7b1a3b90a8edf5d928..6bad4717e0d6ba221eab719595c7633159b730ee 100644
--- a/runtime/bin/file_system_watcher.h
+++ b/runtime/bin/file_system_watcher.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_FILE_SYSTEM_WATCHER_H_
-#define BIN_FILE_SYSTEM_WATCHER_H_
+#ifndef RUNTIME_BIN_FILE_SYSTEM_WATCHER_H_
+#define RUNTIME_BIN_FILE_SYSTEM_WATCHER_H_
 
 #if defined(DART_IO_DISABLED)
 #error "file_system_watcher.h can only be included on builds with IO enabled"
@@ -57,5 +57,5 @@ class FileSystemWatcher {
 }  // namespace bin
 }  // namespace dart
 
-#endif  // BIN_FILE_SYSTEM_WATCHER_H_
+#endif  // RUNTIME_BIN_FILE_SYSTEM_WATCHER_H_