Make getActiveSource in HdmiControlService work for non-TV device.

ag/5463663

Adding a getSafeDeviceInfo() to get the local device info since the
getDeviceInfo() is service thread only.

This device info is returned when the current device is the Active
Source. Otherwise we look for the device info in the remote device list
maintained by the switch device type.

Test: manual
Bug: 119041273
Change-Id: Iaa2e87eaa9e430205a92a30ebd4506a6e8ef5f2b