ART: Fix ARM invoke stub, run Generic JNI in jni_compiler_test

On devices which support it, run all jni compiler tests also with
the Generic JNI infrastructure.

Fix art_quick_invoke_stub for ARM32 to enforce 16B stack alignment.
As the native convention does not require as much, the previous
code would keep it unaligned.

Bug: 17107929
Change-Id: Ibce423949846e447d2b0246d07973b6b717691ac