hg: jdk/sandbox: 8210920: Native C++ tests are not using CXXFLAGS

[chris.hegarty at oracle.com]

Changeset: 43668e3cae4d
Author:    ihse
Date:      2018-09-20 08:59 +0200
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/43668e3cae4d

8210920: Native C++ tests are not using CXXFLAGS
Reviewed-by: tbell, erikj

! make/autoconf/flags-cflags.m4
! make/autoconf/flags-ldflags.m4
! make/autoconf/spec.gmk.in
! make/common/TestFilesCompilation.gmk