hg: jdk/submit: 8209837: Avoid initializing ExpiringCache during bootstrap

[claes.redestad at oracle.com]

Changeset: edcf0d527658
Author:    redestad
Date:      2018-08-24 14:04 +0200
URL:       http://hg.openjdk.java.net/jdk/submit/rev/edcf0d527658

8209837: Avoid initializing ExpiringCache during bootstrap
Reviewed-by: sundar, forax

! src/java.base/share/classes/java/io/FileSystem.java
! src/java.base/unix/classes/java/io/UnixFileSystem.java
! src/java.base/windows/classes/java/io/WinNTFileSystem.java