A flat ArrayBuffer or an array of ArrayBuffers carrying the
binary values of the tensors concatenated in the order specified in
specs.
Specifications of the names, dtypes and shapes of the tensors
whose value are encoded by buffer.
A map from tensor name to tensor value, with the names corresponding
to names in specs.
Decode flat ArrayBuffer as weights.
This function does not handle sharding.
This function is the reverse of
encodeWeights.