Aura overlay scrollbars adjust color for dark backgrounds

third_party/WebKit/Source/platform/scroll/ScrollTypes.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 167 matching lines @@
   BackTrackPart = 1 << 2,
   ThumbPart = 1 << 3,
   ForwardTrackPart = 1 << 4,
   BackButtonEndPart = 1 << 5,
   ForwardButtonEndPart = 1 << 6,
   ScrollbarBGPart = 1 << 7,
   TrackBGPart = 1 << 8,
   AllParts = 0xffffffff
 };
 
-enum ScrollbarOverlayStyle {
-  ScrollbarOverlayStyleDefault,
-  ScrollbarOverlayStyleDark,
-  ScrollbarOverlayStyleLight
+enum ScrollbarOverlayColorTheme {
+  ScrollbarOverlayColorThemeDark,
+  ScrollbarOverlayColorThemeLight
 };
 
 enum ScrollBehavior {
   ScrollBehaviorAuto,
   ScrollBehaviorInstant,
   ScrollBehaviorSmooth,
 };
 
 // The result of an attempt to scroll. If didScroll is true, then
 // unusedScrollDelta gives the amount of the scroll delta that was not consumed
@@ skipping 36 matching lines @@
 
   return (dir == ScrollLeft || dir == ScrollRight) ? ScrollOffset(delta, 0)
                                                    : ScrollOffset(0, delta);
 }
 
 typedef unsigned ScrollbarControlPartMask;
 
 }  // namespace blink
 
 #endif