Don't use algorithm parameters if missing salt or iteration count.

The PBEKeySpec constructor doesn't allow an empty salt or iteration count,
and throws an exception if it sees one.

Bug: 38161557
Test: cts -m CtsLibcoreTestCases

(cherry picked from commit 65832e311cb5fda062d79599b149232b47294fea)

Change-Id: I69d05471af364f69793e83268c826d24ac82052e
Merged-In: I23fa5d10003637584f856738940f54bddb0657dc
Merged-In: I585d00f30e8848563d74d3f244f073d91d5db268
1 file changed