This patch adds (but does not enable the usage of) RefcountedResource
objects to IpSecService, with tests to ensure correct function. This is
patch 1 of a series of patches to refactor the resource management
systems in IpSecService.
RefcountedResource objects allow for management of acyclical dependency
trees, ensuring eventual cleanup when resources are no longer used. This
cleanup may be triggered by binder death or by explicit user action.
Bug: 63409385
Test: New tests written in IpSecServiceRefcountedResourceTest,
explicitly testing the RefcountedResource class
Change-Id: Ib5be7482b2ef5f1c8dec9be68f15e90d8b3aba6d
c926bdefee