Clean up base::Callback stuff

base/bind_unittest.nc

Index: base/bind_unittest.nc
diff --git a/base/bind_unittest.nc b/base/bind_unittest.nc
index fb8f28a3c6d79f8ae8b1d7d6ce5ecacc9fb3c586..70c479f0d08cfc2bd1bc8be1c840f727ad243565 100644
--- a/base/bind_unittest.nc
+++ b/base/bind_unittest.nc
@@ -193,7 +193,7 @@ void WontCompile() {
   weak_ptr_with_non_void_return_type.Run();
 }
 
-#elif defined(NCTEST_DISALLOW_ASSIGN_DIFFERENT_TYPES)  // [r"fatal error: no viable conversion from 'Callback<typename internal::BindState<typename internal::FunctorTraits<void \(\*\)\(int\)>::RunnableType, typename internal::FunctorTraits<void \(\*\)\(int\)>::RunType, internal::TypeList<> >::UnboundRunType>' to 'Callback<void \(\)>'"]
+#elif defined(NCTEST_DISALLOW_ASSIGN_DIFFERENT_TYPES)  // [r"fatal error: no viable conversion from 'Callback<typename internal::BindState<typename internal::FunctorTraits<void \(\*\)\(int\)>::RunnableType, typename internal::FunctorTraits<void \(\*\)\(int\)>::RunType>::UnboundRunType>' to 'Callback<void \(\)>'"]
 
 // Bind result cannot be assigned to Callbacks with a mismatching type.
 void WontCompile() {