logging for the view engine

#1563
@rynowak do we need to log an Error if the application throws an error? 
The `EnsureSuccessful()` on https://github.com/aspnet/Mvc/pull/1660/files#diff-54eb8d65d49bae77d473c5d6f40bcaa0R48 would throw if the view isn't found. Is this something we need to separately log or would we expect an application to log this via some error handling mechanism?