With 50 iterations I'm seeing the following assertion failure:
cairo-hash.c:477: _cairo_hash_table_insert: Assertion `NOT_REACHED' failed.
Thanks to Jan Slupski <jslupski@juljas.net> for pointing out this bug.
Abstract log fie creation into cairo_test_init for use by tests that don't use cairo_test().
Add new test for bug #4299 as reported by Alexey Shabalin.