Summary:
This patch allows parsing generic types, such as Sequence<T>, in XPIDL. It does
this by introducing a new type, TypeId, which contains both the name string and
an optional list of generic parameters.
Various places which use the xpidl.py library had to be updated to construct one
of these TypeId objects, as TypeId and `str` are not compatible types.
Depends On D2106
Reviewers: mccr8!
Tags: #secure-revision
Bug #: 1474369
Differential Revision: https://phabricator.services.mozilla.com/D2109
4d1911e395