Merge pull request #1707 from leobalter/private-methods-args

src/arguments/args-trailing-comma-multiple.case

src/arguments/args-trailing-comma-null.case

src/arguments/args-trailing-comma-single-args.case

src/arguments/args-trailing-comma-spread-operator.case

src/arguments/args-trailing-comma-undefined.case

src/arguments/default/async-gen-func-decl.template

src/arguments/default/async-gen-func-expr.template

src/arguments/default/async-gen-meth.template

src/arguments/default/async-gen-named-func-expr.template

...arguments/default/cls-decl-async-gen-meth-static.template

src/arguments/default/cls-decl-async-gen-meth.template

...s/default/cls-decl-async-private-gen-meth-static.template

...rguments/default/cls-decl-async-private-gen-meth.template

...guments/default/cls-decl-private-gen-meth-static.template

src/arguments/default/cls-decl-private-gen-meth.template

src/arguments/default/cls-decl-private-meth-static.template

src/arguments/default/cls-decl-private-meth.template

...arguments/default/cls-expr-async-gen-meth-static.template

src/arguments/default/cls-expr-async-gen-meth.template

...s/default/cls-expr-async-private-gen-meth-static.template