Whitespace only text nodes need to be reattached when their siblings are reattached

Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 46 matching lines @@
 #include "core/dom/MutationRecord.h"
 #include "core/dom/NamedNodeMap.h"
 #include "core/dom/NodeRenderStyle.h"
 #include "core/dom/NodeRenderingContext.h"
 #include "core/dom/PostAttachCallbacks.h"
 #include "core/dom/PresentationAttributeStyle.h"
 #include "core/dom/PseudoElement.h"
 #include "core/dom/ScriptableDocumentParser.h"
 #include "core/dom/SelectorQuery.h"
 #include "core/dom/Text.h"
-#include "core/dom/WhitespaceChildList.h"
 #include "core/dom/custom/CustomElement.h"
 #include "core/dom/custom/CustomElementRegistrationContext.h"
 #include "core/dom/shadow/InsertionPoint.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/TextIterator.h"
 #include "core/editing/htmlediting.h"
 #include "core/events/EventDispatcher.h"
 #include "core/events/FocusEvent.h"
 #include "core/frame/ContentSecurityPolicy.h"
@@ skipping 1551 matching lines @@
 
             forceCheckOfAnyElementSibling = forceCheckOfAnyElementSibling || (childRulesChanged && hasIndirectAdjacentRules);
         }
     }
     // This loop is deliberately backwards because we use insertBefore in the rendering tree, and want to avoid
     // a potentially n^2 loop to find the insertion point while resolving style. Having us start from the last
     // child and work our way back means in the common case, we'll find the insertion point in O(1) time.
     // Reversing this loop can lead to non-deterministic results in our code to optimize out empty whitespace
     // RenderTexts. We try to put off recalcing their style until the end to avoid this issue.
     // See crbug.com/288225
-    WhitespaceChildList whitespaceChildList(change);
     for (Node* child = lastChild(); child; child = child->previousSibling()) {
+        bool didReattach = false;
         if (child->isTextNode()) {
-            Text* textChild = toText(child);
-            // FIXME: This check is expensive and may negate the performance gained by the optimization of
-            // avoiding whitespace renderers.
-            if (textChild->containsOnlyWhitespace())
-                whitespaceChildList.append(textChild);
-            else
-                textChild->recalcTextStyle(change);
+            didReattach = toText(child)->recalcTextStyle(change);
         } else if (child->isElementNode()) {
             Element* element = toElement(child);
             if (shouldRecalcStyle(change, element)) {
                 parentPusher.push();
-                element->recalcStyle(change);
+                didReattach = element->recalcStyle(change);
             } else if (element->supportsStyleSharing()) {
                 document().styleResolver()->addToStyleSharingList(element);
             }
         }
+        if (didReattach)
+            child->reattachWhitespaceSiblings();
     }
 
-    whitespaceChildList.recalcStyle();
-
     if (shouldRecalcStyle(change, this)) {
         updatePseudoElement(AFTER, change);
         updatePseudoElement(BACKDROP, change);
     }
 }
 
 ElementShadow* Element::shadow() const
 {
     return hasRareData() ? elementRareData()->shadow() : 0;
 }
@@ skipping 1753 matching lines @@
     // Before doing so, we need to resolve issues in HTMLSelectElement::recalcListItems
     // and RenderMenuList::setText. See also https://bugs.webkit.org/show_bug.cgi?id=88405
     if (hasTagName(optionTag) || hasTagName(optgroupTag))
         return false;
     if (FullscreenElementStack::isActiveFullScreenElement(this))
         return false;
     return true;
 }
 
 } // namespace WebCore