Add skia::RefPtr class to wrap ref counted classes from Skia.

ui/views/controls/menu/menu_image_util.cc

Index: ui/views/controls/menu/menu_image_util.cc
diff --git a/ui/views/controls/menu/menu_image_util.cc b/ui/views/controls/menu/menu_image_util.cc
index c45450876b03ccf4c2775a8fa6889935b2cfb0e1..6f8d6166f0c77b559aca43ac3eaacfda4c28b70b 100644
--- a/ui/views/controls/menu/menu_image_util.cc
+++ b/ui/views/controls/menu/menu_image_util.cc
@@ -51,14 +51,13 @@ class RadioButtonImageSource : public gfx::CanvasImageSource {
                             static_cast<int>(kIndicatorSize * kGradientStop));
     gradient_points[2].iset(0, kIndicatorSize);
     SkColor gradient_colors[3] = { kGradient0, kGradient1, kGradient2 };
-    SkShader* shader = SkGradientShader::CreateLinear(
+    skia::RefPtr<SkShader> shader = SkGradientShader::CreateLinear(
         gradient_points, gradient_colors, NULL, arraysize(gradient_points),
         SkShader::kClamp_TileMode, NULL);
     SkPaint paint;
     paint.setStyle(SkPaint::kFill_Style);
     paint.setAntiAlias(true);
-    paint.setShader(shader);
-    shader->unref();
+    paint.setShader(shader.get());
     int radius = kIndicatorSize / 2;
     canvas->sk_canvas()->drawCircle(radius, radius, radius, paint);
     paint.setStrokeWidth(SkIntToScalar(0));
@@ -76,8 +75,7 @@ class RadioButtonImageSource : public gfx::CanvasImageSource {
       shader = SkGradientShader::CreateLinear(
           selected_gradient_points, selected_gradient_colors, NULL,
           arraysize(selected_gradient_points), SkShader::kClamp_TileMode, NULL);
-      paint.setShader(shader);
-      shader->unref();
+      paint.setShader(shader.get());
       paint.setStyle(SkPaint::kFill_Style);
       canvas->sk_canvas()->drawCircle(radius, radius,
                                       kSelectedIndicatorSize / 2, paint);