Fixed error recovery if sizeof is used without parenthesis

Changes made in r192200 fixed PR16992, which requested fixit suggesting
parenthesis if sizeof is followed by type-id. However expression in form
T() followed by ')' was incorrectly considered as a type-id if 'T' is
typedef name. This change fixes this case.

Differential Revision: http://llvm-reviews.chandlerc.com/D2440