Fix aliasing violations only and not c++11 mode:

picked code bits from this change:  https://github.com/SaberMod/android_frameworks_base/commit/4ea79c201e537e5490cc459c7438cf2f7f0c53b4
GC triggering performance optimizations

Copy the correct starting heap size at process init.
Interfaces to set GC/managed heap parameters.

Change-Id: I0154d1523c3cfdb1214ed0315193cbb24704351f