This enhancement makes the generation of random BigIntegers faster, using directly a random generated int[] magnitude array instead of a byte[] array. This permits to call trustedStripLeadingZeroInts() instead of stripLeadingZeroBytes(), in order to avoid copying the contents of the byte[] array in an int[] array if not necessary, since, unlike the previous implementation, the int[] array is not used as an argument by the method of the Random object used to generate random ints. Link to Pull request: https://github.com/openjdk/jdk/pull/12775
