Cache gfx::RenderText instances in views::Label.

ui/gfx/render_text_harfbuzz.cc

 // 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.
 
 #include "ui/gfx/render_text_harfbuzz.h"
 
 #include <limits>
 
 #include "base/i18n/bidi_line_iterator.h"
 #include "base/i18n/break_iterator.h"
@@ skipping 629 matching lines @@
     update_display_text_ = false;
     display_run_list_.reset();
     return layout_text();
   }
 
   EnsureLayoutRunList();
   DCHECK(!update_display_text_);
   return text_elided() ? display_text() : layout_text();
 }
 
+bool RenderTextHarfBuzz::MultilineSupported() const {
+  return true;
+}
+
 Size RenderTextHarfBuzz::GetStringSize() {
   const SizeF size_f = GetStringSizeF();
   return Size(std::ceil(size_f.width()), size_f.height());
 }
 
 SizeF RenderTextHarfBuzz::GetStringSizeF() {
   EnsureLayout();
   return total_size_;
 }
 
@@ skipping 342 matching lines @@
   internal::TextRunList* run_list = GetRunList();
   for (size_t i = 0; i < lines().size(); ++i) {
     const internal::Line& line = lines()[i];
     const Vector2d origin = GetLineOffset(i) + Vector2d(0, line.baseline);
     SkScalar preceding_segment_widths = 0;
     for (const internal::LineSegment& segment : line.segments) {
       const internal::TextRunHarfBuzz& run = *run_list->runs()[segment.run];
       renderer.SetTypeface(run.skia_face.get());
       renderer.SetTextSize(SkIntToScalar(run.font_size));
       renderer.SetFontRenderParams(run.render_params,
-                                   background_is_transparent());
+                                   subpixel_rendering_enabled());
       Range glyphs_range = run.CharRangeToGlyphRange(segment.char_range);
       scoped_ptr<SkPoint[]> positions(new SkPoint[glyphs_range.length()]);
       SkScalar offset_x =
           preceding_segment_widths - run.positions[glyphs_range.start()].x();
       for (size_t j = 0; j < glyphs_range.length(); ++j) {
         positions[j] = run.positions[(glyphs_range.is_reversed()) ?
                                      (glyphs_range.start() - j) :
                                      (glyphs_range.start() + j)];
         positions[j].offset(SkIntToScalar(origin.x()) + offset_x,
                             SkIntToScalar(origin.y()));
@@ skipping 267 matching lines @@
   run->family = font_family;
   run->render_params = params;
 
   // TODO(vadimt): Remove ScopedTracker below once crbug.com/431326 is fixed.
   tracked_objects::ScopedTracker tracking_profile01(
       FROM_HERE_WITH_EXPLICIT_FUNCTION(
           "431326 RenderTextHarfBuzz::ShapeRunWithFont01"));
 
   hb_font_t* harfbuzz_font = CreateHarfBuzzFont(
       run->skia_face.get(), SkIntToScalar(run->font_size), run->render_params,
-      background_is_transparent());
+      subpixel_rendering_enabled());
 
   // TODO(vadimt): Remove ScopedTracker below once crbug.com/431326 is fixed.
   tracked_objects::ScopedTracker tracking_profile1(
       FROM_HERE_WITH_EXPLICIT_FUNCTION(
           "431326 RenderTextHarfBuzz::ShapeRunWithFont1"));
 
   // Create a HarfBuzz buffer and add the string to be shaped. The HarfBuzz
   // buffer holds our text, run information to be used by the shaping engine,
   // and the resulting glyph data.
   hb_buffer_t* buffer = hb_buffer_create();
@@ skipping 146 matching lines @@
   DCHECK(!update_layout_run_list_);
   DCHECK(!update_display_run_list_);
   return text_elided() ? display_run_list_.get() : &layout_run_list_;
 }
 
 const internal::TextRunList* RenderTextHarfBuzz::GetRunList() const {
   return const_cast<RenderTextHarfBuzz*>(this)->GetRunList();
 }
 
 }  // namespace gfx