[LayoutNG] Add NGInlineBreakToken and back of NGInlineLayoutAlgorithm

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

Index: third_party/WebKit/Source/core/layout/ng/ng_line_box_fragment_builder.h
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_line_box_fragment_builder.h b/third_party/WebKit/Source/core/layout/ng/ng_line_box_fragment_builder.h
index 7606b544b16df332715d947ccdad2fb2e3c05f96..da95e4f268e962417e376e3b8eeb67d8cddbb79e 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_line_box_fragment_builder.h
+++ b/third_party/WebKit/Source/core/layout/ng/ng_line_box_fragment_builder.h
@@ -11,6 +11,7 @@
 
 namespace blink {
 
+class NGInlineBreakToken;
 class NGInlineNode;
 class NGPhysicalFragment;
 class NGPhysicalLineBoxFragment;
@@ -36,6 +37,10 @@ class CORE_EXPORT NGLineBoxFragmentBuilder final {
   void UniteMetrics(const NGLineHeightMetrics&);
   const NGLineHeightMetrics& Metrics() const { return metrics_; }
 
+  // Set the break token for the fragment to build.
+  // A finished break token will be attached if not set.
+  void SetBreakToken(RefPtr<NGInlineBreakToken>);
+
   // Creates the fragment. Can only be called once.
   RefPtr<NGPhysicalLineBoxFragment> ToLineBoxFragment();
 
@@ -50,6 +55,8 @@ class CORE_EXPORT NGLineBoxFragmentBuilder final {
   Vector<NGLogicalOffset> offsets_;
 
   NGLineHeightMetrics metrics_;
+
+  RefPtr<NGInlineBreakToken> break_token_;
 };
 
 }  // namespace blink