Back out part of rev 1.24. The intention the quoting backfires and bad

Back out part of rev 1.24. The intention the quoting backfires and bad
quoting is generated. Running 'make all-depends-list' in x11-fonts/libXft
does something like this:
PARENT_CHECKED=/usr/ports/x11-fonts/fontconfig /usr/ports/devel/pkgconfig
/usr/ports/print/freetype2 /usr/ports/devel/gmake /usr/ports/converters/libiconv
/usr/ports/devel/gettext
/usr/ports/devel/libtool13
/usr/ports/devel/libtool15
/usr/ports/textproc/expat2

After quoting this becomes:
PARENT_CHECKED=/usr/ports/x11-fonts/fontconfig\ /usr/ports/devel/pkgconfi
g\
/usr/ports/print/freetype2\ /usr/ports/devel/gmake\ /usr/ports/converters/libico
nv\
/usr/ports/devel/gettext\
/usr/ports/devel/libtool13\
/usr/ports/devel/libtool15\
/usr/ports/textproc/expat2\

The next make tries to do this, the following happens:
before: PARENT_CHECKED=/usr/ports/x11-fonts/fontconfig /usr/ports/devel/pkgconfi
g\
after: PARENT_CHECKED=/usr/ports/x11-fonts/fontconfig\ /usr/ports/devel/pkgconfi
g\\
and the final \\ confuses the shell.

Thanks to asmodai for suggesting a make problem as source.