Use TraceProviderRegistry in //services/dart/dart_tracing.*.

services/dart/dart_tracing.cc

Index: services/dart/dart_tracing.cc
diff --git a/services/dart/dart_tracing.cc b/services/dart/dart_tracing.cc
index 2bee419483767137adb201e5ad1caefa07b72daa..45104c60c7f540639e324d89fa18fc789612d5ec 100644
--- a/services/dart/dart_tracing.cc
+++ b/services/dart/dart_tracing.cc
@@ -8,9 +8,10 @@
 
 #include "dart/runtime/include/dart_tools_api.h"
 #include "mojo/public/cpp/application/application_impl.h"
+#include "mojo/public/cpp/application/connect.h"
 #include "mojo/public/cpp/bindings/interface_handle.h"
 #include "mojo/public/cpp/bindings/interface_request.h"
-#include "mojo/public/interfaces/application/service_provider.mojom.h"
+#include "mojo/services/tracing/interfaces/trace_provider_registry.mojom.h"
 
 namespace dart {
 
@@ -133,19 +134,12 @@ DartTracingImpl::~DartTracingImpl() {
 }
 
 void DartTracingImpl::Initialize(mojo::ApplicationImpl* app) {
-  mojo::InterfaceHandle<mojo::ServiceProvider> outgoing_sp_handle;
-  mojo::InterfaceRequest<mojo::ServiceProvider> outgoing_sp_request =
-      GetProxy(&outgoing_sp_handle);
-  app->shell()->ConnectToApplication("mojo:tracing", nullptr,
-                                     outgoing_sp_handle.Pass());
-  outgoing_sp_for_tracing_service_.Bind(outgoing_sp_request.Pass());
-  outgoing_sp_for_tracing_service_.AddService(this);
-}
+  tracing::TraceProviderRegistryPtr registry;
+  ConnectToService(app->shell(), "mojo:tracing", GetProxy(&registry));
 
-void DartTracingImpl::Create(
-    mojo::ApplicationConnection* connection,
-    mojo::InterfaceRequest<tracing::TraceProvider> request) {
-  provider_impl_.Bind(request.Pass());
+  mojo::InterfaceHandle<tracing::TraceProvider> provider;
+  provider_impl_.Bind(GetProxy(&provider));
+  registry->RegisterTraceProvider(provider.Pass());

[jamesr, 2016/04/28 23:00:28]

this feels like a buncha code that may be repeated a lot with different versions
of |provider_impl_|.  Maybe //mojo/common/ could provide an implementation of
the hookup that just needs a tracing::TraceProvider* ?

 }
 
 }  // namespace dart