findPendingRom answered with the first dump in the save directory whose SHA-1
mapped to any not-yet-ready version. On a device with no file picker that
scan IS the import, so with four dumps in the folder, choosing Red imported
and decoded Blue (#1274).
It now takes an optional version and narrows to it. The two Choose paths
pass self.chooseVersion, since a Choose names the cart it is for. The two
Android USB-drop scans pass nothing and still take the first pending cart of
any version, which is what they are for.
A chosen version with no dump present now imports nothing rather than the
wrong cart, and falls through to the notice that says where to put the file.
bryanthaboi