Stop optimizing dex files when class loaders are created

The background compilation job will take care of optimizing
the loaded dex files.

Test: m test-art-host
      ART_TEST_RUN_TEST_NO_PREBUILD=true m test-art-host-run-test
      art/toos/run-libcore-tests --mode=host
Bug: 32871170

Change-Id: Iab3a933f90bf5fea2240e9df09f932fa017a7905
2 files changed