De-templetize ShapeResultBloberizer

Update ShapeResultBloberizer to remove use of templates and instead call
ToStringView on TextRuns to allow the same implementation to be used for
both legacy layout and LayoutNG. A StringView has extremely low overhead
both in terms of creation and memory usage, should have no perf impact.

Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng
Change-Id: Iaebcb3a5893d619950d1e7cc8c77fcef2015fffe
Reviewed-on: https://chromium-review.googlesource.com/1207095
Reviewed-by: Christian Biesinger <cbiesinger@chromium.org>
Commit-Queue: Emil A Eklund <eae@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589030}

third_party/blink/renderer/platform/fonts/shaping/shape_result_bloberizer.cc

@@ -93,15 +93,15 @@ float ShapeResultBloberizer::FillGlyphs(
       const scoped_refptr<const ShapeResult>& word_result = results[resolved_index];
       word_offset -= word_result->NumCharacters();
       advance =
-          FillGlyphsForResult(word_result.get(), run_info.run, run_info.from,
-                              run_info.to, advance, word_offset);
+          FillGlyphsForResult(word_result.get(), run_info.run.ToStringView(),
+                              run_info.from, run_info.to, advance, word_offset);
     }
   } else {
     unsigned word_offset = 0;
     for (const auto& word_result : results) {
       advance =
-          FillGlyphsForResult(word_result.get(), run_info.run, run_info.from,
-                              run_info.to, advance, word_offset);
+          FillGlyphsForResult(word_result.get(), run_info.run.ToStringView(),
+                              run_info.from, run_info.to, advance, word_offset);
       word_offset += word_result->NumCharacters();
     }
   }
@@ -138,7 +138,7 @@ void ShapeResultBloberizer::FillTextEmphasisGlyphs(
       unsigned resolved_offset =
           word_offset - (run_info.run.Rtl() ? word_result->NumCharacters() : 0);
       advance += FillTextEmphasisGlyphsForRun(
-          word_result->runs_[i].get(), run_info.run,
+          word_result->runs_[i].get(), run_info.run.ToStringView(),
           run_info.run.CharactersLength(), run_info.run.Direction(),
           run_info.from, run_info.to, emphasis_data, advance, resolved_offset);
     }
@@ -164,9 +164,8 @@ void ShapeResultBloberizer::FillTextEmphasisGlyphs(const StringView& text,
 
 namespace {
 
-template <typename TextContainerType>
 inline bool IsSkipInkException(const ShapeResultBloberizer& bloberizer,
-                               const TextContainerType& text,
+                               const StringView& text,
                                unsigned character_index) {
   // We want to skip descenders in general, but it is undesirable renderings for
   // CJK characters.
@@ -175,14 +174,13 @@ inline bool IsSkipInkException(const ShapeResultBloberizer& bloberizer,
              text.CodepointAt(character_index));
 }
 
-template <typename TextContainerType>
 inline void AddGlyphToBloberizer(ShapeResultBloberizer& bloberizer,
                                  float advance,
                                  hb_direction_t direction,
                                  CanvasRotationInVertical canvas_rotation,
                                  const SimpleFontData* font_data,
                                  const HarfBuzzRunGlyphData& glyph_data,
-                                 const TextContainerType& text,
+                                 const StringView& text,
                                  unsigned character_index) {
   FloatPoint start_offset = HB_DIRECTION_IS_HORIZONTAL(direction)
                                 ? FloatPoint(advance, 0)
@@ -243,9 +241,8 @@ inline unsigned CountGraphemesInCluster(const UChar* str,
 
 }  // namespace
 
-template <typename TextContainerType>
 float ShapeResultBloberizer::FillGlyphsForResult(const ShapeResult* result,
-                                                 const TextContainerType& text,
+                                                 const StringView& text,
                                                  unsigned from,
                                                  unsigned to,
                                                  float initial_advance,
@@ -328,10 +325,9 @@ float ShapeResultBloberizer::FillFastHorizontalGlyphs(
   return advance;
 }
 
-template <typename TextContainerType>
 float ShapeResultBloberizer::FillTextEmphasisGlyphsForRun(
     const ShapeResult::RunInfo* run,
-    const TextContainerType& text,
+    const StringView& text,
     unsigned text_length,
     TextDirection direction,
     unsigned from,

third_party/blink/renderer/platform/fonts/shaping/shape_result_bloberizer.h

@@ -108,11 +108,8 @@ class PLATFORM_EXPORT ShapeResultBloberizer {
  private:
   friend class ShapeResultBloberizerTestInfo;
 
-  // Where TextContainerType can be either a TextRun or a StringView.
-  // For legacy layout and LayoutNG respectively.
-  template <typename TextContainerType>
   float FillGlyphsForResult(const ShapeResult*,
-                            const TextContainerType&,
+                            const StringView&,
                             unsigned from,
                             unsigned to,
                             float initial_advance,
@@ -128,9 +125,8 @@ class PLATFORM_EXPORT ShapeResultBloberizer {
   float FillFastHorizontalGlyphs(const ShapeResultBuffer&, TextDirection);
   float FillFastHorizontalGlyphs(const ShapeResult*, float advance = 0);
 
-  template <typename TextContainerType>
   float FillTextEmphasisGlyphsForRun(const ShapeResult::RunInfo*,
-                                     const TextContainerType&,
+                                     const StringView&,
                                      unsigned text_length,
                                      TextDirection,
                                      unsigned from,