Refactor BlockInstance::bulk_delete_artefacts($records)

[Aaron Wells]

See https://mahara.org/interaction/forum/topic.php?id=7465&offset=0&limit=10#post30151. This method is old and has some problems that make it confusing. It'd be nice to clean it up a little. In particular, it has a misleading name (it doesn't delete artefacts; it only de-selects them from block instances). And it has a very particular parameter format that is tightly coupled to a particular SQL query, which could easily be moved inside the function in order to make its API more understandable.

[Mahara Bot (dev-mahara)]

Patch for "master" branch: https://reviews.mahara.org/5911

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/5911
Committed: https://git.mahara.org/mahara/mahara/commit/a618448e03978f58a7d3795e85b3a8f5b57bd54f
Submitter: Son Nguyen (<email address hidden>)
Branch: master

commit a618448e03978f58a7d3795e85b3a8f5b57bd54f
Author: Aaron Wells <email address hidden>
Date: Fri Jan 15 13:10:21 2016 +1300

Bug 1534383 Refactoring BlockInstance::bulk_delete_artefacts()

Renaming to make it less misleading, making its parameters
simpler, and adding some comments to explain how it works

behatnotneeded: Covered by existing tests that delete artefacts

Change-Id: I6091dd4f9cae541a01ddff315629066e0c9df1fb