Render aura scrollbars programmatically instead of with ninebox assets.

ui/native_theme/native_theme_aura.h

Index: ui/native_theme/native_theme_aura.h
diff --git a/ui/native_theme/native_theme_aura.h b/ui/native_theme/native_theme_aura.h
index 8482131ffc38831874083cd0e247d4e0961f0987..d9503f6ab2eaa788ba79e94ed2b91889a6a25a03 100644
--- a/ui/native_theme/native_theme_aura.h
+++ b/ui/native_theme/native_theme_aura.h
@@ -5,16 +5,9 @@
 #ifndef UI_NATIVE_THEME_NATIVE_THEME_AURA_H_
 #define UI_NATIVE_THEME_NATIVE_THEME_AURA_H_
 
-#include <stdint.h>
-
-#include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "ui/native_theme/native_theme_base.h"
 
-namespace gfx {
-class NineImagePainter;
-}
-
 namespace ui {
 
 // Aura implementation of native theme support.
@@ -41,12 +34,12 @@ class NATIVE_THEME_EXPORT NativeThemeAura : public NativeThemeBase {
                         const gfx::Rect& rect,
                         Part direction,
                         State state) const override;
-  void PaintScrollbarTrack(SkCanvas* sk_canvas,
+  void PaintScrollbarTrack(SkCanvas* canvas,
                            Part part,
                            State state,
                            const ScrollbarTrackExtraParams& extra_params,
                            const gfx::Rect& rect) const override;
-  void PaintScrollbarThumb(SkCanvas* sk_canvas,
+  void PaintScrollbarThumb(SkCanvas* canvas,
                            Part part,
                            State state,
                            const gfx::Rect& rect) const override;
@@ -55,73 +48,13 @@ class NATIVE_THEME_EXPORT NativeThemeAura : public NativeThemeBase {
                             const gfx::Rect& rect) const override;
 
   void PaintScrollbarThumbStateTransition(SkCanvas* canvas,
+                                          Part part,
                                           State startState,
                                           State endState,
                                           double progress,
                                           const gfx::Rect& rect) const override;
 
-  // Returns the NineImagePainter used to paint the specified state, creating if
-  // necessary. If no image is provided for the specified state the normal state
-  // images are used.
-  gfx::NineImagePainter* GetOrCreatePainter(
-      const int image_ids[kNumStates][9],
-      State state,
-      scoped_ptr<gfx::NineImagePainter> painters[kNumStates]) const;
-
-  // Paints |painter| into the canvas using |rect|.
-  void PaintPainter(gfx::NineImagePainter* painter,
-                    SkCanvas* sk_canvas,
-                    const gfx::Rect& rect) const;
-
-  mutable scoped_ptr<gfx::NineImagePainter> scrollbar_track_painter_;
-
-  mutable scoped_ptr<gfx::NineImagePainter>
-      scrollbar_thumb_painters_[kNumStates];
-
-  mutable scoped_ptr<gfx::NineImagePainter>
-      scrollbar_arrow_button_painters_[kNumStates];
-
  private:
-  struct DualPainter {
-    // For overlay scrollbar thumbs, fill and stroke are controlled separately,
-    // and each state is achieved by painting with different opacity. This
-    // struct bundles information of painter generated using assets and alpha
-    // value associated with each state, so that a DualPainter for overlay
-    // scrollbar thumb would only need state as input to paint correctly.
-    DualPainter(scoped_ptr<gfx::NineImagePainter> fill_painter,
-                const uint8_t fill_alphas[kNumStates],
-                scoped_ptr<gfx::NineImagePainter> stroke_painter,
-                const uint8_t stroke_alphas[kNumStates]);
-    ~DualPainter();
-
-    scoped_ptr<gfx::NineImagePainter> fill_painter;
-    const uint8_t* const fill_alphas;
-    scoped_ptr<gfx::NineImagePainter> stroke_painter;
-    const uint8_t* const stroke_alphas;
-  };
-
-  // Returns DualPainter from specific fill and stroke, creating if necessary.
-  scoped_ptr<DualPainter> CreateDualPainter(
-      const int fill_image_ids[9],
-      const uint8_t fill_alphas[kNumStates],
-      const int stroke_image_ids[9],
-      const uint8_t stroke_alphas[kNumStates]) const;
-
-  // Paints |dualPainter| into the canvas using |rect| and specific alpha.
-  void PaintDualPainter(DualPainter* dual_painter,
-                        SkCanvas* sk_canvas,
-                        const gfx::Rect& rect,
-                        State state) const;
-
-  void PaintDualPainterTransition(DualPainter* dual_painter,
-                                  SkCanvas* sk_canvas,
-                                  const gfx::Rect& rect,
-                                  State startState,
-                                  State endState,
-                                  double progress) const;
-
-  mutable scoped_ptr<DualPainter> scrollbar_overlay_thumb_painter_;
-
   DISALLOW_COPY_AND_ASSIGN(NativeThemeAura);
 };