Update getSignalStrengthThresholds for multilayer

Update ConnectivityService.getSignalStrengthThresholds so that
thresholds are created for multilayer requests.

Bug: 173650494
Bug: 171991028
Test: atest FrameworksNetTests
atest FrameworksNetIntegrationTests
atest CtsNetTestCasesLatestSdk

Change-Id: Ib3b9f52cf371efd1c7d9b176565c7ea8c46375f1
1 file changed