Adjust Android Keystore AES-GCM test to handle IVs from BC.

This adjusts Android Keystore AES-GCM test to handle the case where
AES/GCM/NoPadding Cipher implementation of the highest priority
provider can generate an IV which is not 12 bytes long. Android
Keystore AES/GCM/NoPadding Cipher implementation only supports 12-byte
IVs. Bouncy Castle's AES/GCM/NoPadding implementation generates
16-byte IVs.

Bug: 22573249
Change-Id: Ia34837162ef374f8ab8203a7c3d2e7bf274ab992
1 file changed