Convert //services from scoped_ptr to std::unique_ptr

services/tracing/public/cpp/tracing_impl.h

Index: services/tracing/public/cpp/tracing_impl.h
diff --git a/services/tracing/public/cpp/tracing_impl.h b/services/tracing/public/cpp/tracing_impl.h
index fa6830409d7d14f42a601e85c30bfb5d8cc44a6b..ed780e5ee4223d4d43a6d2d61c273ce657f32579 100644
--- a/services/tracing/public/cpp/tracing_impl.h
+++ b/services/tracing/public/cpp/tracing_impl.h
@@ -41,7 +41,7 @@ class TracingImpl : public shell::InterfaceFactory<tracing::TraceProvider> {
   void Create(shell::Connection* connection,
               InterfaceRequest<tracing::TraceProvider> request) override;
 
-  scoped_ptr<shell::Connection> connection_;
+  std::unique_ptr<shell::Connection> connection_;
   TraceProviderImpl provider_impl_;
 
   DISALLOW_COPY_AND_ASSIGN(TracingImpl);