Optimize some code in RenderTextHarfbuzz.

ui/gfx/render_text_harfbuzz.h

 // Copyright 2014 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 UI_GFX_RENDER_TEXT_HARFBUZZ_H_
 #define UI_GFX_RENDER_TEXT_HARFBUZZ_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
 #include "third_party/harfbuzz-ng/src/hb.h"
 #include "third_party/icu/source/common/unicode/ubidi.h"
 #include "third_party/icu/source/common/unicode/uscript.h"
 #include "ui/gfx/render_text.h"
 
 namespace base {
 namespace i18n {
 class BreakIterator;
 }
 }
 
 namespace gfx {
 
 class Range;
 class RangeF;
+class RenderTextHarfBuzz;
 
 namespace internal {
 
 struct GFX_EXPORT TextRunHarfBuzz {
   // Construct the run with |template_font| since determining the details of a
   // default-constructed gfx::Font is expensive, but it will always be replaced.
   explicit TextRunHarfBuzz(const Font& template_font);
   ~TextRunHarfBuzz();
 
   // Returns the index of the first glyph that corresponds to the character at
   // |pos|.
   size_t CharToGlyph(size_t pos) const;
 
   // Returns the corresponding glyph range of the given character range.
   // |range| is in text-space (0 corresponds to |GetDisplayText()[0]|). Returned
   // value is in run-space (0 corresponds to the first glyph in the run).
   Range CharRangeToGlyphRange(const Range& range) const;
 
   // Returns the number of missing glyphs in the shaped text run.
   size_t CountMissingGlyphs() const;
 
   // Writes the character and glyph ranges of the cluster containing |pos|.
   void GetClusterAt(size_t pos, Range* chars, Range* glyphs) const;
 
   // Returns the grapheme bounds at |text_index|. Handles multi-grapheme glyphs.
-  RangeF GetGraphemeBounds(base::i18n::BreakIterator* grapheme_iterator,
-                           size_t text_index);
+  RangeF GetGraphemeBounds(RenderTextHarfBuzz* render_text, size_t text_index);
 
   // Returns whether the given shaped run contains any missing glyphs.
   bool HasMissingGlyphs() const;
 
   // Returns the glyph width for the given character range. |char_range| is in
   // text-space (0 corresponds to |GetDisplayText()[0]|).
   SkScalar GetGlyphWidthForCharRange(const Range& char_range) const;
 
   float width;
   float preceding_run_widths;
@@ skipping 83 matching lines @@
   // RenderText:
   std::unique_ptr<RenderText> CreateInstanceOfSameType() const override;
   bool MultilineSupported() const override;
   const base::string16& GetDisplayText() override;
   Size GetStringSize() override;
   SizeF GetStringSizeF() override;
   SelectionModel FindCursorPosition(const Point& point) override;
   std::vector<FontSpan> GetFontSpansForTesting() override;
   Range GetGlyphBounds(size_t index) override;
 
+  // ICU grapheme iterator for the layout text. Can be null in case of an error.
+  base::i18n::BreakIterator* GetGraphemeIterator();
+
  protected:
   // RenderText:
   int GetDisplayTextBaseline() override;
   SelectionModel AdjacentCharSelectionModel(
       const SelectionModel& selection,
       VisualCursorDirection direction) override;
   SelectionModel AdjacentWordSelectionModel(
       const SelectionModel& selection,
       VisualCursorDirection direction) override;
   std::vector<Rect> GetSubstringBounds(const Range& range) override;
@@ skipping 55 matching lines @@
   void ShapeRun(const base::string16& text,
                 internal::TextRunHarfBuzz* run);
   bool ShapeRunWithFont(const base::string16& text,
                         const Font& font,
                         const FontRenderParams& params,
                         internal::TextRunHarfBuzz* run);
 
   // Makes sure that text runs for layout text are shaped.
   void EnsureLayoutRunList();
 
-  // ICU grapheme iterator for the layout text. Can be NULL in case of an error.
-  base::i18n::BreakIterator* GetGraphemeIterator();
-
   // Returns the current run list, |display_run_list_| if the text is
   // elided, or |layout_run_list_| otherwise.
   internal::TextRunList* GetRunList();
   const internal::TextRunList* GetRunList() const;
 
   // Text run list for |layout_text_| and |display_text_|.
   // |display_run_list_| is created only when the text is elided.
   internal::TextRunList layout_run_list_;
   std::unique_ptr<internal::TextRunList> display_run_list_;
 
@@ skipping 11 matching lines @@
 
   // Fixed width of glyphs. This should only be set in test environments.
   float glyph_width_for_test_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderTextHarfBuzz);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_RENDER_TEXT_HARFBUZZ_H_