git: openjdk/mobile: 8179320: File.getUsableSpace() returns a negative number on very large file system

[duke]

Changeset: 4d860947
Author:    Brian Burkhalter <bpb at openjdk.org>
Date:      2019-11-25 15:30:35 +0000
URL:       https://git.openjdk.java.net/mobile/commit/4d860947

8179320: File.getUsableSpace() returns a negative number on very large file system

Reviewed-by: alanb, rriggs, darcy

! src/java.base/share/classes/java/io/File.java