Remove GraphicsLayer::didScroll and directly call ScrollableArea::didScroll

ui/compositor/layer.cc

Index: ui/compositor/layer.cc
diff --git a/ui/compositor/layer.cc b/ui/compositor/layer.cc
index 378a09e96e174d467aaee52c21e8752cdf1963f1..9170fa2d375577aeb0e5c4364b407ace02b8d939 100644
--- a/ui/compositor/layer.cc
+++ b/ui/compositor/layer.cc
@@ -820,8 +820,9 @@ void Layer::OnDelegatedFrameDamage(const gfx::Rect& damage_rect_in_dip) {
     delegate_->OnDelegatedFrameDamage(damage_rect_in_dip);
 }
 
-void Layer::SetScrollable(Layer* parent_clip_layer,
-                          const base::Closure& on_scroll) {
+void Layer::SetScrollable(
+    Layer* parent_clip_layer,
+    const base::Callback<void(const gfx::ScrollOffset&)>& on_scroll) {
   cc_layer_->SetScrollClipLayerId(parent_clip_layer->cc_layer_->id());
   cc_layer_->set_did_scroll_callback(on_scroll);
   cc_layer_->SetUserScrollable(true, true);