Add VDM.createVirtualDisplay

Add the association ID parameter in VDM, and use that to generate the
label for the virtual display name. The association ID check is
currently commented out because the API for companion apps to get the
association ID from CDM is not submitted yet.

Bug: 194949534
Test: Manual
CTS-Coverage-Bug: 204606917
Change-Id: I4d1207fc57a59c8d5b00cc200d507685e7e7a702