Allow sensors list to be empty

Test: atest VtsHalSensorManagerV1_0TargetTest
Bug: 278013275
Bug: 269014004
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:49600b10aa5675d4e7e985203d69f252ead13e45)
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:d9e0d0ad7cb94b2b2d83066685cee45d76381355)
Merged-In: I091f57de9570b0ace3a8da76f16fe0e83f0aa624
Change-Id: I091f57de9570b0ace3a8da76f16fe0e83f0aa624