Helper for interesting things to do when a block becomes a float or out-of-flow.

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

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 2354 matching lines @@
         for (FloatingObjectSetIterator it = fromFloatingObjectSet.begin(); it != end; ++it) {
             const FloatingObject& floatingObject = *it->get();
 
             // Don't insert the object again if it's already in the list
             if (toBlockFlow->containsFloat(floatingObject.layoutObject()))
                 continue;
 
             toBlockFlow->m_floatingObjects->add(floatingObject.unsafeClone());
         }
     }
+}
 
+void LayoutBlockFlow::childBecameFloatingOrOutOfFlow(LayoutBox* child)
+{
+    makeChildrenInlineIfPossible();
+
+    // Reparent the child to an adjacent anonymous block if one is available.
+    LayoutObject* prev = child->previousSibling();
+    if (prev && prev->isAnonymousBlock() && prev->isLayoutBlockFlow()) {
+        LayoutBlockFlow* newContainer = toLayoutBlockFlow(prev);
+        moveChildTo(newContainer, child, nullptr, false);
+        // The anonymous block we've moved to may now be adjacent to former siblings of ours
+        // that it can contain also.
+        newContainer->reparentSubsequentFloatingOrOutOfFlowSiblings();
+        return;
+    }
+    LayoutObject* next = child->nextSibling();
+    if (next && next->isAnonymousBlock() && next->isLayoutBlockFlow()) {
+        LayoutBlockFlow* newContainer = toLayoutBlockFlow(next);
+        moveChildTo(newContainer, child, newContainer->firstChild(), false);
+    }
 }
 
 void LayoutBlockFlow::invalidatePaintForOverhangingFloats(bool paintAllDescendants)
 {
     // Invalidate paint of any overhanging floats (if we know we're the one to paint them).
     // Otherwise, bail out.
     if (!hasOverhangingFloats())
         return;
 
     const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
@@ skipping 1067 matching lines @@
             if (!rect.isEmpty())
                 rects.append(rect);
         }
     }
 
     if (inlineElementContinuation)
         inlineElementContinuation->addOutlineRects(rects, additionalOffset + (inlineElementContinuation->containingBlock()->location() - location()), includeBlockOverflows);
 }
 
 } // namespace blink