Change two helper methods back to be public ones, to fix issues of mocking

them in KeySyncTaskTest.java

I changed them from public to package-private in my last CL. Not sure
whey these issues didn't show up in tests last time

Bug: 112191661
Test: atest FrameworksServicesTests:com.android.server.locksettings.recoverablekeystore
Change-Id: I4e154b8ac5cc353190cc5874ddcd0f9051ea4542