R1:186a12ef7f2a

Replace nonexistent "withPHIDs()" in ChangesetQuery with "withIDs()"

Summary:
Ref T13519. See <https://discourse.phabricator-community.org/t/error-call-to-undefined-method-differentialchangesetquery-withphids/3816/>.

Changesets do not have PHIDs, and the Query has no "withPHIDs()" method. The keys in the viewstate storage are (usually) IDs.

Test Plan:
- On a revision with Diff 1 and Diff 2 affecting the same file:
- Viewed Diff 1.
- Hid file A.
- Viewed Diff 2.
- Before patch: exception…