[LayoutNG] Remove the ng_layout_coordinator and temporary LayoutSync method.

third_party/WebKit/Source/core/layout/ng/ng_layout_algorithm.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 NGLayoutAlgorithm_h
 #define NGLayoutAlgorithm_h
 
 #include "core/CoreExport.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Allocator.h"
 #include "wtf/Noncopyable.h"
 
 namespace blink {
 
 struct MinAndMaxContentSizes;
-class NGBlockNode;
 class NGConstraintSpace;
 class NGPhysicalFragment;
 
 enum NGLayoutStatus { kNotFinished, kChildAlgorithmRequired, kNewFragment };
 
 enum NGLayoutAlgorithmType {
   kBlockLayoutAlgorithm,
   kInlineLayoutAlgorithm,
   kLegacyBlockLayoutAlgorithm,
   kTextLayoutAlgorithm
 };
 
 // Base class for all LayoutNG algorithms.
 class CORE_EXPORT NGLayoutAlgorithm
     : public GarbageCollectedFinalized<NGLayoutAlgorithm> {
   WTF_MAKE_NONCOPYABLE(NGLayoutAlgorithm);
 
  public:
   NGLayoutAlgorithm(NGLayoutAlgorithmType type) : type_(type) {}
   virtual ~NGLayoutAlgorithm() {}
 
   // Actual layout function. Lays out the children and descendents within the
   // constraints given by the NGConstraintSpace. Returns a fragment with the
   // resulting layout information.
-  // This function can not be const because for interruptible layout, we have
-  // to be able to store state information.
-  // If this function returns NotFinished, it has to be called again.
-  // If it returns ChildAlgorithmRequired, the NGBlockNode out parameter will
-  // be set with the NGBlockNode that needs to be layed out next.
-  // If it returns NewFragment, the NGPhysicalFragmentBase out parameter
-  // will contain the new fragment.
-  virtual NGLayoutStatus Layout(NGPhysicalFragment*,
-                                NGPhysicalFragment**,
-                                NGLayoutAlgorithm**) = 0;
+  // TODO(layout-dev): attempt to make this function const.
+  virtual NGPhysicalFragment* Layout() = 0;
 
   enum MinAndMaxState { kSuccess, kPending, kNotImplemented };
 
   // Computes the min-content and max-content intrinsic sizes for the given box.
   // The result will not take any min-width, max-width or width properties into
   // account. Implementations can return false, in which case the caller is
   // expected to synthesize this value from the overflow rect returned from
   // Layout called with a available width of 0 and LayoutUnit::max(),
   // respectively.
   virtual bool ComputeMinAndMaxContentSizes(MinAndMaxContentSizes*) {
     return false;
   }
 
   DEFINE_INLINE_VIRTUAL_TRACE() {}
 
   NGLayoutAlgorithmType algorithmType() const { return type_; }
 
  private:
   NGLayoutAlgorithmType type_;
 };
 
 }  // namespace blink
 
 #endif  // NGLayoutAlgorithm_h