De-client tracing.TraceController interface

services/window_manager/main.cc

Index: services/window_manager/main.cc
diff --git a/services/window_manager/main.cc b/services/window_manager/main.cc
index 893657f68061c26dfa16dbeb411e1ceace6c58a3..a488a935dd3ef3c06fd3f1a83d648b650429dc1f 100644
--- a/services/window_manager/main.cc
+++ b/services/window_manager/main.cc
@@ -36,7 +36,7 @@ class DefaultWindowManager : public mojo::ApplicationDelegate,
   // Overridden from mojo::ApplicationDelegate:
   void Initialize(mojo::ApplicationImpl* impl) override {
     window_manager_app_->Initialize(impl);
-    mojo::TracingImpl::Create(impl);
+    tracing_.Initialize(impl);
   }
   bool ConfigureIncomingConnection(
       mojo::ApplicationConnection* connection) override {
@@ -69,6 +69,7 @@ class DefaultWindowManager : public mojo::ApplicationDelegate,
 
   ViewManager* view_manager_;
   View* root_;
+  mojo::TracingImpl tracing_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(DefaultWindowManager);
 };