[LayoutNG] Remove the state machine from ng_out_of_flow_layout_part.

third_party/WebKit/Source/core/layout/ng/ng_block_node.h

 // 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.
 
 #ifndef NGBlockNode_h
 #define NGBlockNode_h
 
 #include "core/CoreExport.h"
 #include "core/layout/ng/ng_layout_input_node.h"
 #include "platform/heap/Handle.h"
@@ skipping 16 matching lines @@
 
  public:
   explicit NGBlockNode(LayoutObject*);
 
   // TODO(layout-ng): make it private and declare a friend class to use in tests
   explicit NGBlockNode(ComputedStyle*);
 
   ~NGBlockNode() override;
 
   bool Layout(NGConstraintSpace*, NGFragment**) override;
+  void LayoutSync(NGConstraintSpace*, NGFragment**);
+

[atotic, 2017/01/18 18:48:49]

Are Sync methods temporary?

What are our plans for interruptible code? We've thrown out resumable, but
interruptible is still required.

[ikilpatrick, 2017/01/18 19:32:13]

Yup the sync methods are temporary, the eventual Layout() method will be:

NGFragment* Layout(NGConstraintSpace*, NGBreakToken*);

Returning a nullptr from Layout will mean that the parent algorithm should
abort.

Inside each of the algorithms they'll have a macro which does this effectively:

NGLayoutAlgorithm::Layout(/* arguments */) {
  for (child of children) {
    fragment = NG_MAYBE_ABORT(child->Layout(child_space, break_token));
}

NG_MAYBE_ABORT(fragment) {
  if (!fragment) return nullptr;
  if (OutOfTime()) return nullptr;
  return fragment;
}

   NGBlockNode* NextSibling() override;
 
   // Computes the value of min-content and max-content for this box.
   // The return value has the same meaning as for Layout.
   // If the underlying layout algorithm returns NotImplemented from
   // ComputeMinAndMaxContentSizes, this function will synthesize these sizes
   // using Layout with special constraint spaces.
   // It is not legal to interleave a pending Layout() with a pending
   // ComputeOrSynthesizeMinAndMaxContentSizes (i.e. you have to call Layout
   // often enough that it returns true before calling
   // ComputeOrSynthesizeMinAndMaxContentSizes)
   bool ComputeMinAndMaxContentSizes(MinAndMaxContentSizes*);
+  MinAndMaxContentSizes ComputeMinAndMaxContentSizesSync();
 
   const ComputedStyle* Style() const;
   ComputedStyle* MutableStyle();
 
   NGLayoutInputNode* FirstChild();
 
   void SetNextSibling(NGBlockNode*);
   void SetFirstChild(NGLayoutInputNode*);
 
   DECLARE_VIRTUAL_TRACE();
@@ skipping 35 matching lines @@
 
 DEFINE_TYPE_CASTS(NGBlockNode,
                   NGLayoutInputNode,
                   node,
                   node->Type() == NGLayoutInputNode::kLegacyBlock,
                   node.Type() == NGLayoutInputNode::kLegacyBlock);
 
 }  // namespace blink
 
 #endif  // NGBlockNode