[LayoutNG] Refactor NGLineBreaker for ShapingLineBreaker

third_party/WebKit/Source/core/layout/ng/inline/ng_line_breaker.h

Index: third_party/WebKit/Source/core/layout/ng/inline/ng_line_breaker.h
diff --git a/third_party/WebKit/Source/core/layout/ng/inline/ng_line_breaker.h b/third_party/WebKit/Source/core/layout/ng/inline/ng_line_breaker.h
index 79f9d07250c41fea5d3c694f5f4c15efd54c0783..80293583afa7acd04e8381edbbff66f71f22010b 100644
--- a/third_party/WebKit/Source/core/layout/ng/inline/ng_line_breaker.h
+++ b/third_party/WebKit/Source/core/layout/ng/inline/ng_line_breaker.h
@@ -6,24 +6,56 @@
 #define NGLineBreaker_h
 
 #include "core/CoreExport.h"
+#include "core/layout/ng/inline/ng_inline_item_result.h"
 #include "platform/heap/Handle.h"
 #include "platform/wtf/text/AtomicString.h"
 
 namespace blink {
 
+class LazyLineBreakIterator;
+class NGInlineBreakToken;
+class NGInlineItem;
+class NGInlineNode;
 class NGInlineLayoutAlgorithm;
 
 // Represents a line breaker.
+//
+// This class measures each NGInlineItem and determines items to form a line,
+// so that NGInlineLayoutAlgorithm can build a line box from the output.
 class CORE_EXPORT NGLineBreaker {
  public:
-  NGLineBreaker(const AtomicString locale) : locale_(locale) {}
+  NGLineBreaker(NGInlineNode*,
+                const NGConstraintSpace*,
+                NGInlineBreakToken* = nullptr);
   ~NGLineBreaker() {}
   STACK_ALLOCATED();
 
-  void BreakLines(NGInlineLayoutAlgorithm*, const String&, unsigned);
+  // Compute the next line break point and produces NGInlineItemResults for
+  // the line.
+  // TODO(kojii): NGInlineLayoutAlgorithm is needed because floats require
+  // not only constraint space but also container builder. Consider refactor
+  // not to require algorithm.
+  void NextLine(NGInlineItemResults*, NGInlineLayoutAlgorithm*);
+
+  // Create an NGInlineBreakToken for the last line returned by NextLine().
+  RefPtr<NGInlineBreakToken> CreateBreakToken() const;
 
  private:
+  void BreakLine(NGInlineItemResults*, NGInlineLayoutAlgorithm*);
+
+  void LayoutAtomicInline(const NGInlineItem&, NGInlineItemResult*);
+
+  void HandleOverflow(NGInlineItemResults*, const LazyLineBreakIterator&);
+
+  void SkipCollapsibleWhitespaces();
+
+  void AppendCloseTags(NGInlineItemResults*);
+
+  Persistent<NGInlineNode> node_;
+  const NGConstraintSpace* constraint_space_;
   const AtomicString locale_;
+  unsigned item_index_;
+  unsigned offset_;
 };
 
 }  // namespace blink