Fixes ViewManagerClient name in sky

It needs to be mojo::ViewManagerClient; none-the-less we should use
the value from the header so we're insulated from whatever the name
happens to be.

R=hansmuller@google.com, abarth@chromium.org, hansmuller@chromium.org

Review URL: https://codereview.chromium.org/978603002

viewer/BUILD.gn

@@ -47,6 +47,7 @@ mojo_native_application("viewer") {
     "//mojo/services/service_registry/public/interfaces",
     "//mojo/services/surfaces/public/interfaces",
     "//mojo/services/view_manager/public/cpp",
+    "//mojo/services/view_manager/public/interfaces",
     "//skia",
     "//sky/compositor",
     "//sky/engine",

viewer/document_view.cc

@@ -17,6 +17,7 @@
 #include "mojo/public/interfaces/application/shell.mojom.h"
 #include "mojo/services/view_manager/public/cpp/view.h"
 #include "mojo/services/view_manager/public/cpp/view_manager.h"
+#include "mojo/services/view_manager/public/interfaces/view_manager.mojom.h"
 #include "skia/ext/refptr.h"
 #include "sky/compositor/layer.h"
 #include "sky/compositor/layer_host.h"
@@ -369,7 +370,7 @@ void DocumentView::StartDebuggerInspectorBackend() {
 void DocumentView::InitServiceRegistry() {
   mojo::ConnectToService(imported_services_.get(), &service_registry_);
   mojo::Array<mojo::String> interface_names(1);
-  interface_names[0] = "ViewManagerClient";
+  interface_names[0] = mojo::ViewManagerClient::Name_;
   mojo::ServiceProviderImpl* sp_impl(new mojo::ServiceProviderImpl());
   sp_impl->AddService(&view_manager_client_factory_);
   mojo::ServiceProviderPtr sp;