Make EBoxDecorationBreak an enum class.

third_party/WebKit/Source/core/css/CSSPrimitiveValueMappings.h

 /*
  * Copyright (C) 2007 Alexey Proskuryakov <ap@nypop.com>.
  * Copyright (C) 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  * Copyright (C) 2009 Jeff Schiller <codedread@gmail.com>
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ skipping 695 matching lines @@
   }
 
   NOTREACHED();
   return BSTRETCH;
 }
 
 template <>
 inline CSSIdentifierValue::CSSIdentifierValue(EBoxDecorationBreak e)
     : CSSValue(kIdentifierClass) {
   switch (e) {
-    case kBoxDecorationBreakSlice:
+    case EBoxDecorationBreak::kSlice:
       value_id_ = CSSValueSlice;
       break;
-    case kBoxDecorationBreakClone:
+    case EBoxDecorationBreak::kClone:
       value_id_ = CSSValueClone;
       break;
   }
 }
 
 template <>
 inline EBoxDecorationBreak CSSIdentifierValue::ConvertTo() const {
   switch (value_id_) {
     case CSSValueSlice:
-      return kBoxDecorationBreakSlice;
+      return EBoxDecorationBreak::kSlice;
     case CSSValueClone:
-      return kBoxDecorationBreakClone;
+      return EBoxDecorationBreak::kClone;
     default:
       break;
   }
 
   NOTREACHED();
-  return kBoxDecorationBreakSlice;
+  return EBoxDecorationBreak::kSlice;
 }
 
 template <>
 inline CSSIdentifierValue::CSSIdentifierValue(BackgroundEdgeOrigin e)
     : CSSValue(kIdentifierClass) {
   switch (e) {
     case kTopEdge:
       value_id_ = CSSValueTop;
       break;
     case kRightEdge:
@@ skipping 2664 matching lines @@
     default:
       break;
   }
   NOTREACHED();
   return kContainsNone;
 }
 
 }  // namespace blink
 
 #endif