C#: Do flag empty if statements if there is a comment in cs/useless-if-statement.

Author: michaelnebel

csharp/ql/src/Useless code/FutileConditional.ql

@@ -16,7 +16,8 @@ predicate emptyStmt(Stmt s) {
   or
   s =
     any(BlockStmt bs |
-      bs.getNumberOfStmts() = 0
+      bs.getNumberOfStmts() = 0 and
+      not any(CommentBlock cb).getParent() = bs
       or
       bs.getNumberOfStmts() = 1 and
       emptyStmt(bs.getStmt(0))