hg: jdk/sandbox: imported patch factory

[james.laskey at oracle.com]

Changeset: 6a4be8bf8990
Author:    jlaskey
Date:      2019-08-07 15:35 -0300
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/6a4be8bf8990

imported patch factory

! src/java.base/share/classes/java/util/Random.java
! src/java.base/share/classes/java/util/random/RandomGenerator.java
+ src/java.base/share/classes/java/util/random/RandomGeneratorFactory.java