Merge "libdexfile_external is replaced by libdexfile (reland 2)." am: 8146f21745 am: 20df86b2e3 am: 3cabde2819

Original change: https://android-review.googlesource.com/c/platform/system/core/+/1671829

Change-Id: I74c25e5ca981a6fc57438971339345c4839301de