[LayoutNG] Compute baseline from fragment tree

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc.
  *               All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. 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
@@ skipping 1705 matching lines @@
     if (!curr->IsFloatingOrOutOfFlowPositioned()) {
       int result = curr->FirstLineBoxBaseline();
       if (result != -1)
         return (curr->LogicalTop() + result)
             .ToInt();  // Translate to our coordinate space.
     }
   }
   return -1;
 }
 
+bool LayoutBlock::UseLogicalBottomMarginEdgeForInlineBlockBaseline() const {
+  // CSS2.1 states that the baseline of an 'inline-block' is:
+  // the baseline of the last line box in the normal flow, unless it has
+  // either no in-flow line boxes or if its 'overflow' property has a computed
+  // value other than 'visible', in which case the baseline is the bottom
+  // margin edge.
+  // We likewise avoid using the last line box in the case of size containment,
+  // where the block's contents shouldn't be considered when laying out its
+  // ancestors or siblings.
+  return (!Style()->IsOverflowVisible() &&
+          !ShouldIgnoreOverflowPropertyForInlineBlockBaseline()) ||
+         Style()->ContainsSize();
+}
+
 int LayoutBlock::InlineBlockBaseline(LineDirectionMode line_direction) const {
   DCHECK(!ChildrenInline());
-  if ((!Style()->IsOverflowVisible() &&
-       !ShouldIgnoreOverflowPropertyForInlineBlockBaseline()) ||
-      Style()->ContainsSize()) {
+  if (UseLogicalBottomMarginEdgeForInlineBlockBaseline()) {
     // We are not calling LayoutBox::baselinePosition here because the caller
     // should add the margin-top/margin-right, not us.
     return (line_direction == kHorizontalLine ? Size().Height() + MarginBottom()
                                               : Size().Width() + MarginLeft())
         .ToInt();
   }
 
   if (IsWritingModeRoot() && !IsRubyRun())
     return -1;
 
@@ skipping 443 matching lines @@
 bool LayoutBlock::HasDefiniteLogicalHeight() const {
   return AvailableLogicalHeightForPercentageComputation() != LayoutUnit(-1);
 }
 
 bool LayoutBlock::NeedsPreferredWidthsRecalculation() const {
   return (HasRelativeLogicalHeight() && Style()->LogicalWidth().IsAuto()) ||
          LayoutBox::NeedsPreferredWidthsRecalculation();
 }
 
 }  // namespace blink