Fix futures-channel/METADATA am: 5dedceab5a am: 49babae9ee am: dc28ec101c am: 70f7120dc2 am: 8e7c2c6b2e am: 81edf681e0

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/futures-channel/+/1414035

Change-Id: Ie311831cdde100169dba2ae3947b41589eae8c0d