8021203: BigInteger.doubleValue/floatValue returns 0.0 instead of Infinity
8021204: Constructor BigInteger(String val, int radix) doesn't detect overflow
8022780: Incorrect BigInteger division because of MutableBigInteger.bitLength() overflow
Summary: Prevent construction of overflowed BigIntegers.
Reviewed-by: bpb, darcy, psandoz
Contributed-by: NDmitry Nadezhin <dmitry.nadezhin@oracle.com>

Reviewed-by: alanb