Move some reparenting and anonymous block merge functionality down to LayoutBlockFlow.

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 2468 matching lines @@
         newContainer->reparentSubsequentFloatingOrOutOfFlowSiblings();
         return;
     }
     LayoutObject* next = child->nextSibling();
     if (next && next->isAnonymousBlock() && next->isLayoutBlockFlow()) {
         LayoutBlockFlow* newContainer = toLayoutBlockFlow(next);
         moveChildTo(newContainer, child, newContainer->firstChild(), false);
     }
 }
 
+static bool isMergeableAnonymousBlock(const LayoutBlockFlow* block)
+{
+    return block->isAnonymousBlock() && !block->continuation() && !block->beingDestroyed() && !block->isRubyRun() && !block->isRubyBase();
+}
+
+bool LayoutBlockFlow::mergeSiblingContiguousAnonymousBlock(LayoutBlockFlow* siblingThatMayBeDeleted)
+{
+    // Note: |this| and |siblingThatMayBeDeleted| may not be adjacent siblings at this point. There
+    // may be an object between them which is about to be removed.
+
+    if (!isMergeableAnonymousBlock(this) || !isMergeableAnonymousBlock(siblingThatMayBeDeleted))
+        return false;
+
+    setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(LayoutInvalidationReason::AnonymousBlockChange);
+
+    // If the inlineness of children of the two block don't match, we'd need special code here
+    // (but there should be no need for it).
+    ASSERT(siblingThatMayBeDeleted->childrenInline() == childrenInline());
+    // Take all the children out of the |next| block and put them in
+    // the |prev| block.
+    siblingThatMayBeDeleted->moveAllChildrenIncludingFloatsTo(this, siblingThatMayBeDeleted->hasLayer() || hasLayer());
+    // Delete the now-empty block's lines and nuke it.
+    siblingThatMayBeDeleted->deleteLineBoxTree();
+    siblingThatMayBeDeleted->destroy();
+    return true;
+}
+
+void LayoutBlockFlow::reparentSubsequentFloatingOrOutOfFlowSiblings()
+{
+    if (!parent() || !parent()->isLayoutBlockFlow())
+        return;
+    if (beingDestroyed() || documentBeingDestroyed())
+        return;
+    LayoutBlockFlow* parentBlockFlow = toLayoutBlockFlow(parent());
+    LayoutObject* child = nextSibling();
+    while (child && child->isFloatingOrOutOfFlowPositioned()) {
+        LayoutObject* sibling = child->nextSibling();
+        parentBlockFlow->moveChildTo(this, child, nullptr, false);
+        child = sibling;
+    }
+
+    if (LayoutObject* next = nextSibling()) {
+        if (next->isLayoutBlockFlow())
+            mergeSiblingContiguousAnonymousBlock(toLayoutBlockFlow(next));
+    }
+}
+
+void LayoutBlockFlow::reparentPrecedingFloatingOrOutOfFlowSiblings()
+{
+    if (!parent() || !parent()->isLayoutBlockFlow())
+        return;
+    if (beingDestroyed() || documentBeingDestroyed())
+        return;
+    LayoutBlockFlow* parentBlockFlow = toLayoutBlockFlow(parent());
+    LayoutObject* child = previousSibling();
+    while (child && child->isFloatingOrOutOfFlowPositioned()) {
+        LayoutObject* sibling = child->previousSibling();
+        parentBlockFlow->moveChildTo(this, child, firstChild(), false);
+        child = sibling;
+    }
+}
+
 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();
     FloatingObjectSetIterator end = floatingObjectSet.end();
     for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
@@ skipping 1065 matching lines @@
             if (!rect.isEmpty())
                 rects.append(rect);
         }
     }
 
     if (inlineElementContinuation)
         inlineElementContinuation->addOutlineRects(rects, additionalOffset + (inlineElementContinuation->containingBlock()->location() - location()), includeBlockOverflows);
 }
 
 } // namespace blink