rails/strong_parameters — pull request #171 by kennyj (2013-09-29 14:19:00+00:00)
Title: Strong parameters should permit nested number as key. Fixes Rails Issue 12293.

See https://github.com/rails/rails/pull/12354.

Strong parameters should permit nested number as key.
Fields for style presume a value to be hash.
But a value sometimes is string.