Use sk_sp-based shader creation APIs

ui/views/style/mac/combobox_background_mac.cc

 // Copyright 2016 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/views/style/mac/combobox_background_mac.h"
 
 #include "third_party/skia/include/core/SkPath.h"
 #include "third_party/skia/include/core/SkRRect.h"
 #include "ui/gfx/canvas.h"
 #include "ui/native_theme/native_theme_mac.h"
@@ skipping 13 matching lines @@
   gfx::RectF bounds(combobox->GetLocalBounds());
   // Inset the left side far enough to draw only the arrow button, and inset the
   // other three sides by half a pixel so the edge of the background doesn't
   // paint outside the border.
   bounds.Inset(bounds.width() - combobox->GetArrowButtonWidth(), 0.5, 0.5, 0.5);
 
   ui::NativeTheme::State state = ui::NativeTheme::kNormal;
   if (!combobox->enabled())
     state = ui::NativeTheme::kDisabled;
 
-  skia::RefPtr<SkShader> shader =
+  SkPaint paint;
+  paint.setShader(
       ui::NativeThemeMac::GetButtonBackgroundShader(
           state,
-          bounds.height());
-  SkPaint paint;
-  paint.setShader(shader.get());
+          bounds.height()));
   paint.setStyle(SkPaint::kFill_Style);
   paint.setAntiAlias(true);
 
   SkPoint no_curve = SkPoint::Make(0, 0);
   SkPoint curve = SkPoint::Make(
       ui::NativeThemeMac::kComboboxCornerRadius,
       ui::NativeThemeMac::kComboboxCornerRadius);
   SkVector curves[4] = { no_curve, curve, curve, no_curve };
 
   SkRRect fill_rect;
   fill_rect.setRectRadii(gfx::RectFToSkRect(bounds), curves);
 
   SkPath path;
   path.addRRect(fill_rect);
 
   canvas->DrawPath(path, paint);
 }
 
 }  // namespace views