Blacklist arbitrary @\\w+ JSDoc tags from wrapping.

Summary:
Also limits the blacklisting to only apply when the tag is actually
followed by a parameter in curly braces.

    /** @mods {long.type.must.not.wrap} */

vs

    /** @const this is a long description that may wrap. */

Reviewers: djasper

Subscribers: klimek, krasimir, cfe-commits

Differential Revision: https://reviews.llvm.org/D30452

llvm-svn: 296467