Patch the SQLite backend to fix Alter Table breakages.
Review Request #10869 — Created Jan. 29, 2020 and submitted
When running SQLite 2.26+ and Django 1.11 through 2.1.4, an Alter Table
would fail silently, causing problems further down the line. This was
due to some behavioral changes in SQLite when altering tables that
Django was not compatible with.
Django 2.1.4 turns on the
legacy_alter_tableflag when preparing to
edit schema. We now patch earlier versions of Django to do the same
Tested in a Python environment with these versions and reproduced
the problem and the fix.