hg: jdk/sandbox: Lots of structural rearrangements. Also fix for adding EXTRA_FLAGS to BUILD

[magnus.ihse.bursie at oracle.com]

Changeset: b3e3a12dcb33
Author:    ihse
Date:      2018-02-26 14:10 +0100
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/b3e3a12dcb33

Lots of structural rearrangements. Also fix for adding EXTRA_FLAGS to BUILD
flags.

! make/autoconf/configure.ac
! make/autoconf/flags-cflags.m4
! make/autoconf/flags-ldflags.m4
! make/autoconf/flags-other.m4
! make/autoconf/flags.m4