git: openjdk/jdk11u-dev: 8210920: Native C++ tests are not using CXXFLAGS

[Christoph Langer]

Changeset: 426906b8
Author:    Christoph Langer <clanger at openjdk.org>
Date:      2021-09-23 16:06:45 +0000
URL:       https://git.openjdk.java.net/jdk11u-dev/commit/426906b8f8c88ce4ac67eafb05ea42acdfc56f85

8210920: Native C++ tests are not using CXXFLAGS

Reviewed-by: mdoerr
Backport-of: 481a045635fd3cafadf2e5314570b1bf6e45ba89

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