RenderTextHarfBuzz: Allow mid-glyph cursors in multi-grapheme clusters

ui/gfx/render_text.h

Index: ui/gfx/render_text.h
diff --git a/ui/gfx/render_text.h b/ui/gfx/render_text.h
index 9fb6151697bf12b04fd6739792f595f283f0a2df..4234e4da18387ff56427f275eb987dbe879447d3 100644
--- a/ui/gfx/render_text.h
+++ b/ui/gfx/render_text.h
@@ -37,6 +37,12 @@ struct SkPoint;
 class SkShader;
 class SkTypeface;
 
+namespace base {
+namespace i18n {
+class BreakIterator;
+}
+}
+
 namespace gfx {
 
 class Canvas;
@@ -432,6 +438,10 @@ class GFX_EXPORT RenderText {
   const std::vector<internal::Line>& lines() const { return lines_; }
   void set_lines(std::vector<internal::Line>* lines) { lines_.swap(*lines); }
 
+  base::i18n::BreakIterator* grapheme_iterator() {
+      return grapheme_iterator_.get();

[msw, 2014/07/25 00:37:00]

nit: fix indent

[ckocagil, 2014/07/29 23:13:41]

Done.

+  }
+
   // Returns the baseline of the current text.  The return value depends on
   // the text and its layout while the return value of GetBaseline() doesn't.
   // GetAlignmentOffset() takes into account the difference between them.
@@ -705,6 +715,9 @@ class GFX_EXPORT RenderText {
   // ResetLayout and on |display_rect_| changes.
   std::vector<internal::Line> lines_;
 
+  // ICU grapheme iterator for the layout text. Can be NULL in case of an error.
+  scoped_ptr<base::i18n::BreakIterator> grapheme_iterator_;

[msw, 2014/07/25 00:37:00]

Move this to RenderTextHarfBuzz if it's only used in that impl for now. You
should be able to initalize it on ItemizeText, right?

[ckocagil, 2014/07/29 23:13:41]

Done.

+
   DISALLOW_COPY_AND_ASSIGN(RenderText);
 };