Revert "core: add AST support"

This reverts commit 864a84c157f13c9e200d3f68241e62420df3fb27.

Change-Id: Ib30e8ff3dd5ead3b25eda23b78bdcfcf4881cd6f
Merge "Revert "core: add AST support"" into cm-11.0
Merge remote-tracking branch 'upstream/cm-11.0' into cm-11.0