Make EUserSelect an enum class.

third_party/WebKit/Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  *               (http://www.torchmobile.com/)
@@ skipping 1374 matching lines @@
 
   for (const LayoutObject* child = SlowFirstChild(); child;
        child = child->NextSibling())
     child->ShowLayoutTreeAndMark(marked_object1, marked_label1, marked_object2,
                                  marked_label2, depth + 1);
 }
 
 #endif  // NDEBUG
 
 bool LayoutObject::IsSelectable() const {
-  return !IsInert() && !(Style()->UserSelect() == SELECT_NONE &&
+  return !IsInert() && !(Style()->UserSelect() == EUserSelect::kNone &&
                          Style()->UserModify() == EUserModify::kReadOnly);
 }
 
 Color LayoutObject::SelectionBackgroundColor() const {
   if (!IsSelectable())
     return Color::kTransparent;
 
   if (RefPtr<ComputedStyle> pseudo_style = GetUncachedSelectionStyle())
     return ResolveColor(*pseudo_style, CSSPropertyBackgroundColor)
         .BlendWithWhite();
@@ skipping 2242 matching lines @@
     const blink::LayoutObject* root = object1;
     while (root->Parent())
       root = root->Parent();
     root->ShowLayoutTreeAndMark(object1, "*", object2, "-", 0);
   } else {
     WTFLogAlways("%s", "Cannot showLayoutTree. Root is (nil)");
   }
 }
 
 #endif