If the enclosing environment does not implement ConfigurableEnvironment,
then @PropertySource annotations are ignored because there is no way to
add them to the Environment. Now checking first to see if there are any
@PropertySource annotations present before issuing the warning.
Issue: SPR-8314
git-svn-id: https://src.springframework.org/svn/spring-framework/trunk@4295 50f2f4bb-b051-0410-bef5-90022cba6387