Cleaning up some dead code which has been here for 9 years. They are
never detected by Lint because we still initialize them as `None` but
never change afterwards.
Testing: No regression.
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Signed-off-by: Euclid Ye <euclid.ye@huawei.com>
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>