Convert USERSELECT_ALL to a runtime enabled feature.

Source/core/dom/Position.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2009 Apple 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 834 matching lines @@
 bool Position::nodeIsUserSelectNone(Node* node)
 {
     return node && node->renderer() && node->renderer()->style()->userSelect() == SELECT_NONE && node->renderer()->style()->userModify() == READ_ONLY;
 }
 
 ContainerNode* Position::findParent(const Node* node)
 {
     return node->parentNode();
 }
 
-#if ENABLE(USERSELECT_ALL)
 bool Position::nodeIsUserSelectAll(const Node* node)
 {
-    return node && node->renderer() && node->renderer()->style()->userSelect() == SELECT_ALL;
+    return RuntimeEnabledFeatures::userSelectAllEnabled() && node && node->renderer() && node->renderer()->style()->userSelect() == SELECT_ALL;
 }
 
 Node* Position::rootUserSelectAllForNode(Node* node)
 {
     if (!node || !nodeIsUserSelectAll(node))
         return 0;
     Node* parent = node->parentNode();
     if (!parent)
         return node;
 
     Node* candidateRoot = node;
     while (parent) {
         if (!parent->renderer()) {
             parent = parent->parentNode();
             continue;
         }
         if (!nodeIsUserSelectAll(parent))
             break;
         candidateRoot = parent;
         parent = candidateRoot->parentNode();
     }
     return candidateRoot;
 }
-#endif
 
 bool Position::isCandidate() const
 {
     if (isNull())
         return false;
 
     RenderObject* renderer = deprecatedNode()->renderer();
     if (!renderer)
         return false;
 
@@ skipping 499 matching lines @@
     pos.showTreeForThis();
 }
 
 void showTree(const WebCore::Position* pos)
 {
     if (pos)
         pos->showTreeForThis();
 }
 
 #endif