Revert "Revert "Track libcore update of Map classes to jdk8u60""

Automerger issues have been resolved. This change needs
to be rolled forward once Automerger merges
http://r.android.com/255655 from mirror-aosp-master into
stage-aosp-master.

This reverts commit 77832136.

Change-Id: I16e1d94351ccf7cc1aeb8f9905410cd23514e8ff