(unary_expr, expr_no_commas): Increment skip_evaluation when analyzing an expression...

(unary_expr, expr_no_commas): Increment skip_evaluation when analyzing an expression that is known not to be evaluated.

(unary_expr, expr_no_commas): Increment skip_evaluation when analyzing an
expression that is known not to be evaluated.
(sizeof, alignof): New rules.

From-SVN: r13231