[not for review - epic CL] Adding Elastic+Momentum+Layered scrolling to views::ScrollView

ui/compositor/layer.cc

 // Copyright (c) 2012 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 "ui/compositor/layer.h"
 
 #include <algorithm>
 #include <memory>
 #include <utility>
 
@@ skipping 726 matching lines @@
 }
 
 void Layer::OnDelegatedFrameDamage(const gfx::Rect& damage_rect_in_dip) {
   DCHECK(surface_layer_.get());
   if (delegate_)
     delegate_->OnDelegatedFrameDamage(damage_rect_in_dip);
 }
 
 void Layer::SetScrollable(Layer* parent_clip_layer,
                           const base::Closure& on_scroll) {
-  cc_layer_->SetScrollClipLayerId(parent_clip_layer->cc_layer_->id());
+  cc_layer_->SetScrollClipAndCanOverscroll(parent_clip_layer->cc_layer_->id(),
+                                           true /* can_overscroll */);
   cc_layer_->set_did_scroll_callback(on_scroll);
   cc_layer_->SetUserScrollable(true, true);
 }
 
 gfx::ScrollOffset Layer::CurrentScrollOffset() const {
   const Compositor* compositor = GetCompositor();
   gfx::ScrollOffset offset;
   if (compositor &&
       compositor->GetScrollOffsetForLayer(cc_layer_->id(), &offset))
     return offset;
@@ skipping 312 matching lines @@
   if (animator_) {
     animator_->DetachLayerAndTimeline(compositor);
     animator_->RemoveFromCollection(collection);
   }
 
   for (auto* child : children_)
     child->ResetCompositorForAnimatorsInTree(compositor);
 }
 
 }  // namespace ui