Fix very long app_name crash.

http://ibrahimbalic.com/2014/android-os-memory-corruption-bug/ found an stack overflow bug.
The very long app_name make libandroid_runtime allocate a very large array on stack, the stack may overflow to other data areas in this situation.
This patch allocate large array on heap instead of on stack to avoid segment fault when doing memcpy.

Change-Id: I99999569b852d43a9c7a6eb1fa80e9f1a1f4e2b2
Merge "Fix very long app_name crash." into du44