SI-8350 treat single parens equivalently to no-parens in new

q"new C" and q"new C()" have identical trees after parsing. This
commit adds knowledge of this invariant to SyntacticNew.
SI-8387 don't match new as a function application
Merge pull request #3656 from densh/si/8387-8350

SI-8350 SI-8387 tweak handling of new trees