Fix debugging on dalvik.

u4* args is a pointer to a flat array of 4 byte values,
so the "debugFlags" arg of postForkChild(long, int debugFlags)
is at args[2], not args[1].

bug: 13926783

Change-Id: Icd3bbf9dd249cdd70e085acdd4dd7daa415cd698
Merge "Fix debugging on dalvik."
auto-merger: merge in from aosp/master