Revert "Update LTO patchset for mr2 merge"

This reverts commit 6c4b9fe9b619fbeb9969cc6387e5024ce8fa3b27.
Revert "Android.mk: disable LTO"

This reverts commit a69dce07cce43a15b34324ca46ed79849598ccf3.
Remove LOCAL_CLANG (build with cfX Clang 3.4)