Merge "libdexfile_external is replaced by libdexfile (reland)." am: e29c64b029 am: e7cd98c643 am: c5dc64adf5

Original change: https://android-review.googlesource.com/c/platform/system/core/+/1664030

Change-Id: I8e8da217064e63d0f27a2a8a8c655dc031a8526a