Fix some memory leaks in AuraLinux tests

These are typically caused by ATK GObjects that are reffed, but then
never unreffed.

Bug: 961578
Change-Id: I6455044685f7253b6088ddaf32e611eaa97971f2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1605402
Reviewed-by: Joanmarie Diggs <jdiggs@igalia.com>
Commit-Queue: Martin Robinson <mrobinson@igalia.com>
Cr-Commit-Position: refs/heads/master@{#658483}
2 files changed