Replace use of SkLerpXfermode with SkArithmeticMode

ui/views/controls/button/label_button_border.cc

 // Copyright (c) 2012 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/controls/button/label_button_border.h"
 
 #include "base/logging.h"
 #include "third_party/skia/include/core/SkPaint.h"
-#include "third_party/skia/include/effects/SkLerpXfermode.h"
+#include "third_party/skia/include/effects/SkArithmeticMode.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/animation/animation.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/gfx/sys_color_change_listener.h"
 #include "ui/native_theme/native_theme.h"
 #include "ui/resources/grit/ui_resources.h"
 #include "ui/views/border.h"
 #include "ui/views/controls/button/label_button.h"
@@ skipping 121 matching lines @@
   ui::NativeTheme::State state = native_theme_delegate->GetThemeState(&extra);
 
   if (animation && animation->is_animating()) {
     // Linearly interpolate background and foreground painters during animation.
     const SkRect sk_rect = gfx::RectToSkRect(rect);
     canvas->sk_canvas()->saveLayer(&sk_rect, NULL);
     state = native_theme_delegate->GetBackgroundThemeState(&extra);
     PaintHelper(this, canvas, state, rect, extra);
 
     SkPaint paint;
-    skia::RefPtr<SkXfermode> sk_lerp_xfer =
-        skia::AdoptRef(SkLerpXfermode::Create(animation->GetCurrentValue()));
-    paint.setXfermode(sk_lerp_xfer.get());
+    double scale = animation->GetCurrentValue();
+    skia::RefPtr<SkXfermode> sk_arith_xfer =
+        skia::AdoptRef(SkArithmeticMode::Create(0.0f, scale, 1.0 - scale, 0.0));
+    paint.setXfermode(sk_arith_xfer.get());
     canvas->sk_canvas()->saveLayer(&sk_rect, &paint);
     state = native_theme_delegate->GetForegroundThemeState(&extra);
     PaintHelper(this, canvas, state, rect, extra);
     canvas->sk_canvas()->restore();
 
     canvas->sk_canvas()->restore();
   } else {
     PaintHelper(this, canvas, state, rect, extra);
   }
 }
@@ skipping 14 matching lines @@
   return painters_[focused ? 1 : 0][state].get();
 }
 
 void LabelButtonAssetBorder::SetPainter(bool focused,
                                         Button::ButtonState state,
                                         Painter* painter) {
   painters_[focused ? 1 : 0][state].reset(painter);
 }
 
 }  // namespace views