Make header include guards great again

runtime/vm/scavenger.h

Index: runtime/vm/scavenger.h
diff --git a/runtime/vm/scavenger.h b/runtime/vm/scavenger.h
index 798470cf936e968b06c78565721d1ec6a207bedb..caa2dafa5cf1466a5c3e34a3592c863fe5ca054a 100644
--- a/runtime/vm/scavenger.h
+++ b/runtime/vm/scavenger.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 VM_SCAVENGER_H_
-#define VM_SCAVENGER_H_
+#ifndef RUNTIME_VM_SCAVENGER_H_
+#define RUNTIME_VM_SCAVENGER_H_
 
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ -312,4 +312,4 @@ class Scavenger {
 
 }  // namespace dart
 
-#endif  // VM_SCAVENGER_H_
+#endif  // RUNTIME_VM_SCAVENGER_H_