phpcs: Normalize methods declarations to "[final abstract] [visibility]".

CodeSniffer sniff is:
  [abstract final] [<visibility>] [static] function
As declared by:
  PSR2.Methods.MethodDeclaration.StaticBeforeVisibility
in:
  https://github.com/wikimedia/mediawiki-tools-codesniffer/blob/master/MediaWiki/ruleset.xml


Change-Id: Ifabd289e8668019ed752bdd711b3b43a9c346336
Merge "phpcs: Normalize methods declarations to "[final abstract] [visibility]"."