Implements core logic for Pixel Canvas

ui/compositor/layer.cc

Index: ui/compositor/layer.cc
diff --git a/ui/compositor/layer.cc b/ui/compositor/layer.cc
index 3a2aa4fc0a72a329c02ea4b51ec4eb194a146bce..12fd95727e62356d4ef331a9f34906fb6a270c0a 100644
--- a/ui/compositor/layer.cc
+++ b/ui/compositor/layer.cc
@@ -919,8 +919,10 @@ scoped_refptr<cc::DisplayItemList> Layer::PaintContentsToDisplayList(
   paint_region_.Clear();
   auto display_list = make_scoped_refptr(new cc::DisplayItemList);
   if (delegate_) {
-    delegate_->OnPaintLayer(
-        PaintContext(display_list.get(), device_scale_factor_, invalidation));
+    display_list->set_pixel_canvas_enabled(ui::IsPixelCanvasRecordingEnabled());
+    PaintContext context(display_list.get(), device_scale_factor_, invalidation,
+                         size());
+    delegate_->OnPaintLayer(context);
   }
   display_list->Finalize();
   // TODO(domlaskowski): Move mirror invalidation to Layer::SchedulePaint.