* Fix type keyword completions
1. In functions, type keywords were omitted.
2. In All context, no keywords were omitted.
(1) fixes#28737
(2) removes 17 keywords that should not be suggested, even at the
toplevel of a typescript file:
* private
* protected
* public
* static
* abstract
* as
* constructor
* get
* infer
* is
* namespace
* require
* set
* type
* from
* global
* of
I don't know whether we have a bug tracking this or not.
* Change keyword filter in filterGlobalCompletion
Instead of changing FunctionLikeBodyKeywords
* Add more tests cases
* Make type-only completions after < more common
Because isPossiblyTypeArgumentPosition doesn't give false positives now
that it uses type information.