rails/rails — pull request #8458 by lucisferre (2012-12-08 00:01:32+00:00)
Title: Provides standard layout lookup behavior for method and proc cases

When setting the layout either by referencing a method with a symbol or supplying a Proc there is no way to fall back to the default lookup behavior if desired instead returning nil will render no template.

This patch changes this behavior so that returning nil from either a method or a proc will result in the default template lookup.