Add logic for recording dex files use on disk

Add PackageDexUsage to handle the I/O operations of dex usage data. It
is responsible to encode, save and load dex

Test: runtest -x .../PackageDexUsageTests.java

Bug: 32871170
Change-Id: I2acc5430080a7e937c798513d8959ab631decfd9
4 files changed