Switch back to the old Android viaduct backend (backport #7093)

[mergify]

We've been seeing a large volume of crashes on android (https://bugzilla.mozilla.org/show_bug.cgi?id=1992149). They seem to be related to the new viaduct backend. It's unclear exactly why, but let's try going back to the old one and see if it lessens the volume.

This reverts commit 2042b47 so that we can use the old backend code.

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This is an automatic backport of pull request #7093 done by [Mergify](https://mergify.com).