[layoutng] Add helper functions to compute lengths

third_party/WebKit/Source/core/layout/ng/ng_block_layout_algorithm.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/layout/ng/ng_block_layout_algorithm.h"
 
 #include "core/layout/LayoutBox.h"
 #include "core/layout/ng/ng_constraint_space.h"
 #include "core/layout/ng/ng_fragment.h"
+#include "core/layout/ng/ng_length_utils.h"
 #include "core/style/ComputedStyle.h"
 #include "platform/LengthFunctions.h"
 
 namespace blink {
 
 NGBlockLayoutAlgorithm::NGBlockLayoutAlgorithm(
     PassRefPtr<const ComputedStyle> style,
     NGBox firstChild)
     : m_style(style), m_firstChild(firstChild) {}
 
 NGFragment* NGBlockLayoutAlgorithm::layout(
     const NGConstraintSpace& constraintSpace) {
-  LayoutUnit inlineSize = valueForLength(m_style->logicalWidth(),
-                                         constraintSpace.inlineContainerSize());
-  LayoutUnit blockSize = valueForLength(m_style->logicalHeight(),
-                                        constraintSpace.blockContainerSize());
+  LayoutUnit inlineSize =
+      computeInlineSizeForFragment(constraintSpace, *m_style);
 
   for (NGBox curr = m_firstChild; curr; curr.nextSibling()) {
     curr.layout(constraintSpace);
   }
 
+  LayoutUnit blockSize =
+      computeBlockSizeForFragment(constraintSpace, *m_style, LayoutUnit());
   return new NGFragment(inlineSize, blockSize, inlineSize, blockSize);
 }
 
 }  // namespace blink