Reject dex files that attempt to use unspecified class access flags

Change-Id: Ib1ecf3dfe1856a9014c2e9b0d6a1725ba7617f98
Move verification of class access flags to libdex

Change-Id: I020a168cfff46e319b0bebb6c7477f0b4139c6de
Use -fno-strict-aliasing for libdvm

Change-Id: If971e7020cc32a4b22b62bfac474c1d9e0945fa8