Call server based implementation to persist reboot escrow key

Adds the implementation for RebootEscrowProviderServerBased. It will
bind to the resume on reboot service on device; and ask the server
to encrypt/decrypt the reboot escrow key.

Bug: 172780686
Test: atest FrameworksServicesTests:RebootEscrowDataTest \
            FrameworksServicesTests:LockSettingsServiceTests \
            FrameworksServicesTests:RebootEscrowManagerTests \
            FrameworksServicesTests:RebootEscrowProviderServerBasedImplTests;

Change-Id: I6f301314ba43eb106e67d849bfe14e80c607403f