As it stands now, action=query&list=recentchanges (or &generator=recentchanges) allows filtering of pages only by title using (g)rctitle.
Add another option to filter pages by (g)rcpageid.
This resolves a practical problem: retrieving props for a page that was moved shows only props of the new title, but not props for the old title. This is especially noticeable for retrieving unpatrolled revisions of the page.
Retrieving the title via mw.config.get("wgPageName") will only return unpatrolled revisions after the move (if any), while any unpatrolled revisions before the move will not be returned because they are tied to the old title.
Page ID is a primary key, and is therefore not affected by the move, so filtering recent changes by pageid would resolve this problem.