[LayoutNG] Fixes small crash inside preferred widths.

third_party/WebKit/Source/core/layout/ng/ng_block_node.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_node.h"
 
 #include "core/layout/LayoutBlock.h"
 #include "core/layout/LayoutBlockFlow.h"
 #include "core/layout/LayoutMultiColumnFlowThread.h"
 #include "core/layout/LayoutMultiColumnSet.h"
@@ skipping 210 matching lines @@
   return nullptr;
 }
 
 bool NGBlockNode::CanUseNewLayout() const {
   // [Multicol]: for the 1st phase of LayoutNG's multicol implementation we want
   // to utilize the existing ColumnBalancer class. That's why a multicol block
   // should be processed by Legacy Layout engine.
   if (Style().SpecifiesColumns())
     return false;
 
-  if (!box_->IsLayoutBlockFlow())
+  if (!box_->IsLayoutNGBlockFlow())
     return false;
+
   return RuntimeEnabledFeatures::LayoutNGEnabled();

[cbiesinger, 2017/06/15 17:37:57]

Do we need this or can it be return true;?

[ikilpatrick, 2017/06/15 18:05:33]

It can be true at the moment, but want to leave this in as we'll need to for if
we do:

LayoutListItem : public LayoutNGBlockFlow { }

(and LayoutNGBlockFlow has a bunch of:
LayoutNGBlockFlow::Foo() {
  if (!RuntimeEnabledFeatures::LayoutNGEnabled())
    LayoutBlockFlow::Foo();
}

 }
 
 String NGBlockNode::ToString() const {
   return String::Format("NGBlockNode: '%s'",
                         GetLayoutObject()->DebugName().Ascii().data());
 }
 
 void NGBlockNode::CopyFragmentDataToLayoutBox(
     const NGConstraintSpace& constraint_space,
     NGLayoutResult* layout_result) {
@@ skipping 112 matching lines @@
 
 // Save static position for legacy AbsPos layout.
 void NGBlockNode::SaveStaticOffsetForLegacy(const NGLogicalOffset& offset) {
   DCHECK(box_->IsOutOfFlowPositioned());
   DCHECK(box_->Layer());
   box_->Layer()->SetStaticBlockPosition(offset.block_offset);
   box_->Layer()->SetStaticInlinePosition(offset.inline_offset);
 }
 
 }  // namespace blink