This adds the materialized literal count accumulated while parsing the
parameters (in the parser proper) to that accumulated by the preparser.

This should have been caught in cctest/test-parsing, but it's not covered
because the parsing tests call directly into the preparser rather than
using Parser::ParseFunctionLiteral (which fully-parses the parameters
and then calls into the preparser to skip over the function body).

Note that this further-inflates the materialized literal count for
functions with destructured arguments, since some of the counted
literals are actually binding patterns. But that's not specific to
binding patterns in formal parameters: it happens in function bodies, too.

BUG=v8:4400,v8:4407
LOG=n

Review URL: https://codereview.chromium.org/1350913005

Cr-Commit-Position: refs/heads/master@{#30868}