Merge "Exec_start derive_classpath on post-fs-data." am: 294167d436 am: 5a9cc5be96 am: d42c33e586

Original change: https://android-review.googlesource.com/c/platform/system/core/+/1602393

Change-Id: Ifd306f2bb2c5f56eac97aec22d5c11a885040c4f