Fail FUSE_LOOKUP if transcoding file pre-allocation fails

Previously, we tried to fail gracefully by trying to treat the node as
if it doesn't require transcoding. This was hacky and might lead to
hard to debug issues. Now, we fail fast if pre-allocation (unlikely in
itself) fails

Test: Manual
Bug: 183174642
Change-Id: I98ca89e4ca1ab7e299df0142a405bf9820d4eaaa
1 file changed