Bug 1153109 - Add -D_GLIBCXX_USE_CXX11_ABI=0 to CXXFLAGS when building with --enable-stdcxx-compat. r=nfroyd

configure.in

@@ -7385,6 +7385,8 @@ if test -n "$STDCXX_COMPAT"; then
    eval $(CXX="$CXX" HOST_CXX="$HOST_CXX" $PYTHON -m mozbuild.configure.libstdcxx)
    AC_SUBST(MOZ_LIBSTDCXX_TARGET_VERSION)
    AC_SUBST(MOZ_LIBSTDCXX_HOST_VERSION)
+   CXXFLAGS="$CXXFLAGS -D_GLIBCXX_USE_CXX11_ABI=0"
+   HOST_CXXFLAGS="$HOST_CXXFLAGS -D_GLIBCXX_USE_CXX11_ABI=0"
 fi
 
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