Adds more to viewmanager

mojo/examples/sample_view_manager_app/sample_view_manager_app.cc

Index: mojo/examples/sample_view_manager_app/sample_view_manager_app.cc
diff --git a/mojo/examples/sample_view_manager_app/sample_view_manager_app.cc b/mojo/examples/sample_view_manager_app/sample_view_manager_app.cc
index c6d6e7c77952576e44ea0c109f9aa0fb4b8ee19b..cbb3c2ba278f20d0aee7aebae988f7d2ed12192b 100644
--- a/mojo/examples/sample_view_manager_app/sample_view_manager_app.cc
+++ b/mojo/examples/sample_view_manager_app/sample_view_manager_app.cc
@@ -51,6 +51,11 @@ class SampleApp : public Application,
                                       uint32_t old_parent,
                                       int32_t change_id) OVERRIDE {
   }
+  virtual void OnNodeViewChanged(uint32_t node,
+                                 uint32_t old_view_id,
+                                 uint32_t new_view_id,
+                                 int32_t change_id) OVERRIDE {
+  }
 
  private:
   void OnCreatedView(bool success) {