Pass a ui::PaintContext from ui::Layer to layer delegates.

content/browser/web_contents/aura/shadow_layer_delegate.cc

 // Copyright (c) 2013 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 "content/browser/web_contents/aura/shadow_layer_delegate.h"
 
 #include "base/bind.h"
 #include "third_party/skia/include/effects/SkGradientShader.h"
 #include "ui/aura/window.h"
 #include "ui/compositor/layer.h"
+#include "ui/compositor/paint_context.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/skia_util.h"
 
 namespace {
 
 const SkColor kShadowLightColor = SkColorSetARGB(0x0, 0, 0, 0);
 const SkColor kShadowDarkColor = SkColorSetARGB(0x70, 0, 0, 0);
 const int kShadowThick = 7;
 
 }  // namespace
 
 namespace content {
 
 ShadowLayerDelegate::ShadowLayerDelegate(ui::Layer* shadow_for)
     : layer_(new ui::Layer(ui::LAYER_TEXTURED)) {
   layer_->set_delegate(this);
   layer_->SetBounds(gfx::Rect(-kShadowThick, 0, kShadowThick,
                               shadow_for->bounds().height()));
   layer_->SetFillsBoundsOpaquely(false);
   shadow_for->Add(layer_.get());
 }
 
 ShadowLayerDelegate::~ShadowLayerDelegate() {
 }
 
-void ShadowLayerDelegate::OnPaintLayer(gfx::Canvas* canvas) {
+void ShadowLayerDelegate::OnPaintLayer(const ui::PaintContext& context) {
   SkPoint points[2];
   const SkColor kShadowColors[2] = { kShadowLightColor, kShadowDarkColor };
 
   points[0].iset(0, 0);
   points[1].iset(kShadowThick, 0);
 
   skia::RefPtr<SkShader> shader = skia::AdoptRef(
       SkGradientShader::CreateLinear(points, kShadowColors, NULL,
           arraysize(points), SkShader::kRepeat_TileMode));
 
   gfx::Rect paint_rect = gfx::Rect(0, 0, kShadowThick,
                                    layer_->bounds().height());
   SkPaint paint;
   paint.setShader(shader.get());
-  canvas->sk_canvas()->drawRect(gfx::RectToSkRect(paint_rect), paint);
+  context.canvas()->sk_canvas()->drawRect(gfx::RectToSkRect(paint_rect), paint);
 }
 
 void ShadowLayerDelegate::OnDelegatedFrameDamage(
     const gfx::Rect& damage_rect_in_dip) {
 }
 
 void ShadowLayerDelegate::OnDeviceScaleFactorChanged(float scale_factor) {
 }
 
 base::Closure ShadowLayerDelegate::PrepareForLayerBoundsChange() {
   return base::Bind(&base::DoNothing);
 }
 
 }  // namespace content