Change default GCM name to AES/GCM/NOPADDING

This matches the RI and doesn't get late binding confused when you call
Cipher.getInstance

(cherry picked from commit 4046cd0249e7ffa820dcd4318f4e81f737d8634c)

Bug: 21085702
Change-Id: I8f69e7b342fde4881f20e103240f0b289322ef4e
2 files changed