Work around gold bug in Tor Browser

While bisecting on my Debian box I am always hitting https://bugzilla.mozilla.org/show_bug.cgi?id=1233963. We should backport the fix to include it at least in the alpha series. Given that https://hg.mozilla.org/mozilla-central/rev/1a4c479ec7cd is pretty simple having this one in the stable series as well can't hurt.

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