Remove OatWriter::DexFileSource am: a8a815cb3a am: 51478e1584 am: d56932fb80

Original change: https://android-review.googlesource.com/c/platform/art/+/2422726

Change-Id: I9de2b062aa45cc8d5041d681ecd54c3909919684
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>