When a statement is dropped from the AST because it was invalid, make sure
we don't do the scope checks otherwise we are going to hit assertion checks
since a label may not have been actually added.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175281 91177308-0d34-0410-b5e6-96231b3b80d8
Fix crash-on-invalid where a ParenListExpr shows up as a message receiver
while trying to do error recovery.

rdar://13207886

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175282 91177308-0d34-0410-b5e6-96231b3b80d8