Update from https://crrev.com/311076

cc/resources/display_item.cc

Index: cc/resources/display_item.cc
diff --git a/cc/resources/display_item.cc b/cc/resources/display_item.cc
index 33069a53fdf27f60efe5c6f43caf4f707c83a4d5..52bdec12667534584bd1000b6c10f7b849670ca8 100644
--- a/cc/resources/display_item.cc
+++ b/cc/resources/display_item.cc
@@ -9,4 +9,8 @@ namespace cc {
 DisplayItem::DisplayItem() {
 }
 
+void DisplayItem::RasterForTracing(SkCanvas* canvas) const {
+  Raster(canvas, nullptr);
+}
+
 }  // namespace cc