Floats are also out-of-flow considering white-space.

third_party/WebKit/Source/core/dom/Text.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
  * reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 277 matching lines @@
   unsigned maxSiblingsToVisit = 50;
 
   const LayoutObject* prev =
       LayoutTreeBuilderTraversal::previousSiblingLayoutObject(
           *this, maxSiblingsToVisit);
   if (prev && prev->isBR())  // <span><br/> <br/></span>
     return false;
 
   if (parent.isLayoutInline()) {
     // <span><div/> <div/></span>
-    if (prev && !prev->isInline() && !prev->isOutOfFlowPositioned())
+    if (prev && !prev->isInline() && !prev->isFloatingOrOutOfFlowPositioned())
       return false;
   } else {
     if (parent.isLayoutBlock() && !parent.childrenInline() &&
         (!prev || !prev->isInline()))
       return false;
 
     LayoutObject* first = parent.slowFirstChild();
     for (; first && first->isFloatingOrOutOfFlowPositioned() &&
            maxSiblingsToVisit;
          first = first->nextSibling(), --maxSiblingsToVisit) {
@@ skipping 153 matching lines @@
 
 Text* Text::cloneWithData(const String& data) {
   return create(document(), data);
 }
 
 DEFINE_TRACE(Text) {
   CharacterData::trace(visitor);
 }
 
 }  // namespace blink