R1:4b6da9735ba7

Remove overbearing policy checks in Phame

Summary:
Fixes T11584. This controller does unnecessary CAN_EDIT policy checks.

These checks are enforced by `EditEngine`, and you can make certain types of edits (including comments) even without full-blown edit permission.

Test Plan:
- Commented as a user without edit permission.
- Tried to edit as a user without edit permission, was rebuffed with a policy dialog.
- Edited as a user with edit permission.

Reviewers: chad

Reviewed By: chad

Maniphest…