Move idmap to frameworks/base [1/2]

idmap depends on libandroidfw, so it should go in frameworks/base.
This follows AOSP which moved idmap to frameworks/base back in
February of 2014.

Change-Id: If86df906bddf987fd58e31f947ae78ddd0d2c666
Merge branch 'master' of https://github.com/AOSB/android_frameworks_native