xfce4-panel revision 20070 won't build.

make[2]: *** No rule to make target `xfce-panel-convenience.c', needed by
`libxfce4panel_la-xfce-panel-convenience.lo'.  Stop.
make[2]: Leaving directory
`/opt/xfce4-svn/src/xfce4svn/xfce4-panel/trunk/libxfce4panel'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/opt/xfce4-svn/src/xfce4svn/xfce4-panel/trunk'
make: *** [all] Error 2

Reproducible: Always
Steps to Reproduce: