Log watchdog events using logging parent name.

Bug: 148002608
Test: manually tested using two apk X and Y as following:
    1. Added meta-data to X stating Y is the logging parent for X.
    2. Installed both with --staged and --enable-rollback flag.
    3. On boot complete, crashed the system server 5 times.
    4. Observed on logcat that events were logged under Y.
Test: Ran the same test as above but this time, without any meta-data.
      Events were logged twice for each package on boot.
Test: Installed the apks separately so that there were multiple
      rollbacks. Events were logged properly.
Change-Id: I3b3e0a46afa9cc2a7eecb9932e3cd8a123a1c416