Current uses:https://codesearch.wmflabs.org/search/?q=issemiprotected&i=fosho&files=&repos=

See alsoT230103,T45462#473199,T169626(probably need to fix first)

This means:

• Instead of "semiprotectedpagewarning" and "semiprotectedpagemovewarning", we have a message for each protection level.
• Instead of using CSS class mw-textarea-sprotected, each protection level use one CSS class, (and probably also an additional CSS class for all protected pages regardless of level)
• instead using isSemiProtected function, extensions should use getRestrictions to get the actual protection level.