swift234

Lexer: Special-case 'super' and 'constructor'.
Dave noted that he's trying to scrub the parser codebase of wishy-washy 'isAnyLParen' and 'isAnyLBrace' calls by consistently lexing opening bracket tokens correctly to begin with. Since currently only 'super' and 'constructor' need to be lexed like identifiers for expression syntax (and, in the future, 'this' and 'This' when those become keywords), mark them as a special kind of 'identifier keyword' in Tokens.def and roll back some of the changes I made to make parsing other decls support either token.

Swift SVN r3848