Convert //cc from scoped_ptr to std::unique_ptr.

cc/layers/painted_scrollbar_layer.cc

Index: cc/layers/painted_scrollbar_layer.cc
diff --git a/cc/layers/painted_scrollbar_layer.cc b/cc/layers/painted_scrollbar_layer.cc
index b94766655d1c698aa39f9167a8ecec726d3874af..4f4b84d77a3eb074f896d8cccc3bcaa56685e3ff 100644
--- a/cc/layers/painted_scrollbar_layer.cc
+++ b/cc/layers/painted_scrollbar_layer.cc
@@ -24,21 +24,22 @@
 
 namespace cc {
 
-scoped_ptr<LayerImpl> PaintedScrollbarLayer::CreateLayerImpl(
+std::unique_ptr<LayerImpl> PaintedScrollbarLayer::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
   return PaintedScrollbarLayerImpl::Create(
       tree_impl, id(), scrollbar_->Orientation());
 }
 
 scoped_refptr<PaintedScrollbarLayer> PaintedScrollbarLayer::Create(
-    scoped_ptr<Scrollbar> scrollbar,
+    std::unique_ptr<Scrollbar> scrollbar,
     int scroll_layer_id) {
   return make_scoped_refptr(
       new PaintedScrollbarLayer(std::move(scrollbar), scroll_layer_id));
 }
 
-PaintedScrollbarLayer::PaintedScrollbarLayer(scoped_ptr<Scrollbar> scrollbar,
-                                             int scroll_layer_id)
+PaintedScrollbarLayer::PaintedScrollbarLayer(
+    std::unique_ptr<Scrollbar> scrollbar,
+    int scroll_layer_id)
     : scrollbar_(std::move(scrollbar)),
       scroll_layer_id_(scroll_layer_id),
       internal_contents_scale_(1.f),