Revert "Add interface to query the mmap support."

This reverts commit 57c44c00.

Bug: 198836727
Reason for revert: DroidMonitor-triggered revert due to breakage https://android-build.googleplex.com/builds/quarterdeck?branch=git_master&target=adt3-userdebug&lkgb=7703400&lkbb=7703573&fkbb=7703552

Change-Id: I82b9b99f8ab31134873157819fdb341cfa65ac80