Add Filters to format strings for Private and Protected Posts in get_the_title

[anderswc]

When a page or post is protected or private, WordPress prefixes its title with either "Protected: " or "Private: " when get_the_title() is called.

This patch changes get_the_title to call filters for the format strings that add prefixes to protected and private posts. Plugins and themes can filter the format strings to remove or change the prefix.

[Denis-de-Bernardy]

won't be needed if #6284 gets checked in

[Denis-de-Bernardy]

Actually, nm that. :-)

But #9666 would certainly do the trick, in that it would allow to str_replace() the formatting afterwards.

[Denis-de-Bernardy]

see r11112