Themes page should have search subtitle

[kawauso]

Most admin pages display the term that the user has searched for when displaying search results, but the Themes page (under site admin) doesn't.

[16525] seems to have excluded it in the AJAXified list tables, but gives no reasoning.

[kawauso]

Subtitle based on Comments screen code

[ocean90]

We decided to remove the subtitle because it's not the right place. The search is after the Current Theme info and the subtitle before.

See also #15553.

[c3mdigital]

Search subtitle moved in #15553. Closing ticket.