Replace IntArray with List<Integer> (3/n)

Per discussion of go/modularize-rollbackmanager, module code can't use
hidden APIs. Considering CPU and memory impact, we decide to replace
IntArray with List<Integer> to get rid of the use of hidden APIs.

Bug: 150347230
Test: atest RollbackUnitTest
      atest RollbackStoreTest
      atest AppDataRollbackHelperTest
Change-Id: Ica3b0d3bd0eb930cc6cb89f06a7dd9a89202fcf3