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

chrome/browser/chromeos/ui/focus_ring_layer.cc

Index: chrome/browser/chromeos/ui/focus_ring_layer.cc
diff --git a/chrome/browser/chromeos/ui/focus_ring_layer.cc b/chrome/browser/chromeos/ui/focus_ring_layer.cc
index 812055e056333816d3f5eb5da6444ae12d15e6e5..c0ca65fe7990d8cb3106fe58b08e8d0013ce67ea 100644
--- a/chrome/browser/chromeos/ui/focus_ring_layer.cc
+++ b/chrome/browser/chromeos/ui/focus_ring_layer.cc
@@ -7,6 +7,7 @@
 #include "base/bind.h"
 #include "ui/aura/window.h"
 #include "ui/compositor/layer.h"
+#include "ui/compositor/paint_context.h"
 #include "ui/gfx/canvas.h"
 
 namespace chromeos {
@@ -56,10 +57,11 @@ void FocusRingLayer::CreateOrUpdateLayer(
   layer_->parent()->StackAtTop(layer_.get());
 }
 
-void FocusRingLayer::OnPaintLayer(gfx::Canvas* canvas) {
+void FocusRingLayer::OnPaintLayer(const ui::PaintContext& context) {
   if (!root_window_ || focus_ring_.IsEmpty())
     return;
 
+  gfx::Canvas* canvas = context.canvas();
   gfx::Rect bounds = focus_ring_ - layer_->bounds().OffsetFromOrigin();
   SkPaint paint;
   paint.setColor(kShadowColor);