[LayoutNG] Remove an unused member function of NGPhysicalLineBoxFragment

The function is unused after crrev.com/c/1000952. It's also a bad-designed
function due to the requirement of a seemingly redundant parameter.

Hence, this patch removes it.

Bug: 822575
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_layout_tests_layout_ng
Change-Id: Iefdc4a9f6cde0d8f5edfc6d4c75750b1655f6c39
Reviewed-on: https://chromium-review.googlesource.com/1007973Reviewed-by: Aleks Totic <atotic@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550241}

third_party/blink/renderer/core/layout/ng/inline/ng_physical_line_box_fragment.cc

@@ -87,14 +87,6 @@ bool NGPhysicalLineBoxFragment::HasSoftWrapToNextLine() const {
   return !break_token.IsFinished() && !break_token.IsForcedBreak();
 }
 
-// TODO(xiaochengh): Try avoid passing |previous_line|.
-bool NGPhysicalLineBoxFragment::HasSoftWrapFromPreviousLine(
-    const NGPhysicalLineBoxFragment* previous_line) const {
-  if (!previous_line)
-    return false;
-  return previous_line->HasSoftWrapToNextLine();
-}
-
 PositionWithAffinity NGPhysicalLineBoxFragment::PositionForPoint(
     const NGPhysicalOffset& point) const {
   return PositionForPointInInlineLevelBox(point);

third_party/blink/renderer/core/layout/ng/inline/ng_physical_line_box_fragment.h

@@ -47,10 +47,6 @@ class CORE_EXPORT NGPhysicalLineBoxFragment final
   // Whether the content soft-wraps to the next line.
   bool HasSoftWrapToNextLine() const;
 
-  // Whether the content is following a soft-wrap from the previous line.
-  // TODO(xiaochengh): Try to avoid passing the previous line.
-  bool HasSoftWrapFromPreviousLine(const NGPhysicalLineBoxFragment*) const;
-
   PositionWithAffinity PositionForPoint(const NGPhysicalOffset&) const final;
 
   scoped_refptr<NGPhysicalFragment> CloneWithoutOffset() const {