Transfer data directly to the device (#5752)
* Remove `populate_fn` from `TensorSource`
* Make TensorSource an interface
* Re-enable pjrt_computation_client_test
* server -> device
* add comment
* fix outbound data metric
* formatting
* implement byte_strides in TensorSource
* more formatting
* remove extra deps
* add missing deps
* Revert "server -> device"
This reverts commit 63845167bbb81a42ecc73dc5835868befd1baa0f.
