Can't create a share from a snapshot with the snapshot name

Steps to reproduce:
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0) Setup manila with a backend that supports snapshots and creating shares from snapshots (Ex: LVM, Dummy drivers)
1) Create a share type with extra-specs "snapshot_support=True" and "create_share_from_snapshot_support=True"
2) Create a share with the share type created in step 1
3) Create a snapshot of this share, name it "testsnap"
4) Attempt to create a share from this snapshot:

manila create nfs 1 --snapshot testsnap

Expected Result:
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Share gets created

Actual Result:
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This error is shown:
ERROR: ShareSnapshotNotFound: Snapshot testsnap could not be found.

RCA:
---
When using the "--debug" switch to study the request, we see this:

$ manila --debug create nfs 1 --snapshot testsnap

<snip>
DEBUG (httpclient:192)
REQ: curl -i -X POST http://10.10.10.13:8786/v2/5332f831ce1c4aebb295ad4bd4a9cd2f/shares -H "X-Openstack-Manila-Api-Version: 2.46" -H "X-Auth-Token: gAAAAABbxonsLHr_xZONqCsPieSzaX2YbrdNMZFxRgISe2QZb8-BLchAuBUXroWWE7vWviqWmyCZylnL6w26J2zFWzjncJ6c-3oLHO-P77SkDXI4OqGPkJW2RBcDwePfP8HT1F7gCwvA-MRYGvU8bYLjDzHWLlhb4svetHz4uBBNU0nNRuoPcso" -H "Content-Type: application/json" -H "Accept: application/json" -H "User-Agent: python-manilaclient" -d '{"share": {"name": null, "share_type": null, "snapshot_id": "testsnap", "availability_zone": null, "is_public": false, "description": null, "metadata": {}, "share_proto": "nfs", "share_network_id": null, "size": 1}}'

DEBUG (connectionpool:205) Starting new HTTP connection (1): 10.10.10.13:8786
DEBUG (connectionpool:393) http://10.10.10.13:8786 "POST /v2/5332f831ce1c4aebb295ad4bd4a9cd2f/shares HTTP/1.1" 404 106
RESP: [404] {'Content-Length': '106', 'x-compute-request-id': 'req-10720cdf-a50a-43aa-9470-1c05dd4f26f6', 'Vary': 'X-OpenStack-Manila-API-Version', 'Connection': 'close', 'Server': 'Apache/2.4.29 (Ubuntu)', 'X-OpenStack-Manila-API-Version': '2.46', 'Date': 'Wed, 17 Oct 2018 01:01:32 GMT', 'Content-Type': 'application/json'}
RESP BODY: {"itemNotFound": {"message": "ShareSnapshotNotFound: Snapshot testsnap could not be found.", "code": 404}}

DEBUG (httpclient:201) RESP: [404] {'Content-Length': '106', 'x-compute-request-id': 'req-10720cdf-a50a-43aa-9470-1c05dd4f26f6', 'Vary': 'X-OpenStack-Manila-API-Version', 'Connection': 'close', 'Server': 'Apache/2.4.29 (Ubuntu)', 'X-OpenStack-Manila-API-Version': '2.46', 'Date': 'Wed, 17 Oct 2018 01:01:32 GMT', 'Content-Type': 'application/json'}
RESP BODY: {"itemNotFound": {"message": "ShareSnapshotNotFound: Snapshot testsnap could not be found.", "code": 404}}

As observed, the client is not converting the name to the snapshot's ID before sending the share creation request