Make PhabricatorPolicyInterface require a getPHID() method
Summary:
Ref T603. This cleans up an existing callsite in the policy filter, and opens up some stuff in the future.
Some policy objects don't have real PHIDs:
PhabricatorTokenGiven
PhabricatorSavedQuery
PhabricatorNamedQuery
PhrequentUserTime
PhabricatorFlag
PhabricatorDaemonLog
PhabricatorConduitMethodCallLog
ConduitAPIMethod
PhabricatorChatLogEvent
PhabricatorChatLogChannel
Although it would be reasonable to add real PHIDs to some of these (like `ChatLogChannel`), it probably doesn't make much sense for others (`DaemonLog`, `MethodCallLog`). Just let them return `null`.
Also remove some duplicate `$id` and `$phid` properties. These are declared on `PhabricatorLiskDAO` and do not need to be redeclared.
Test Plan: Ran the `testEverythingImplemented` unit test, which verifies that all classes conform to the interface.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T603
Differential Revision: https://secure.phabricator.com/D7306