Convert USERSELECT_ALL to a runtime enabled feature.

Source/core/dom/Node.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 634 matching lines @@
 {
     if (isPseudoElement())
         return false;
 
     // Ideally we'd call ASSERT(!needsStyleRecalc()) here, but
     // ContainerNode::setFocus() calls setNeedsStyleRecalc(), so the assertion
     // would fire in the middle of Document::setFocusedNode().
 
     for (const Node* node = this; node; node = node->parentNode()) {
         if ((node->isHTMLElement() || node->isDocumentNode()) && node->renderer()) {
-#if ENABLE(USERSELECT_ALL)
             // Elements with user-select: all style are considered atomic
             // therefore non editable.
-            if (node->renderer()->style()->userSelect() == SELECT_ALL && treatment == UserSelectAllIsAlwaysNonEditable)
+            if (RuntimeEnabledFeatures::userSelectAllEnabled() && node->renderer()->style()->userSelect() == SELECT_ALL && treatment == UserSelectAllIsAlwaysNonEditable)

[adamk, 2013/08/09 21:42:32]

Rather than sprinkling these RuntimeEnabledFeatures checks around, is there some
way to keep style()->userSelect() from ever returning SELECT_ALL if the flag is
off? That seems like a more maintainable approach to runtime flags like this.

[ojan, 2013/08/09 22:10:10]

This code doesn't add a new css value, it changes the behavior of the existing
one. That said, I was able to get rid of a bunch of the sprinkled checks by
using Position::nodeIsUserSelectAll in more places.

                 return false;
-#else
-            UNUSED_PARAM(treatment);
-#endif
             switch (node->renderer()->style()->userModify()) {
             case READ_ONLY:
                 return false;
             case READ_WRITE:
                 return true;
             case READ_WRITE_PLAINTEXT_ONLY:
                 return editableLevel != RichlyEditable;
             }
             ASSERT_NOT_REACHED();
             return false;
@@ skipping 2069 matching lines @@
         node->showTreeForThis();
 }
 
 void showNodePath(const WebCore::Node* node)
 {
     if (node)
         node->showNodePathForThis();
 }
 
 #endif