swift234

Change TopLevelCodeDecl to allow it to hold a sequence of different exprs and statements in one unit, wrapping them into a BraceStmt.  This makes it more similar to other decls (e.g. funcdecl, ctor decls, etc) and will be useful for future sil work.

Unfortunately, this regresses the repl when expressions like (1,2) are entered. This is because the repl is violating some invariants (forming dags out of ASTs, making ASDAG's which upset the type checker).  I'm going to fix this next, but can't bring myself to do it in the same commit.



Swift SVN r4617