ewmh: implement support for _NET_WORKAREA (rdesktop can use that)

Please note that rdesktop’s -g workarea option will not work on
64-bit systems at the moment because of a bug in rdesktop (see the
rdesktop-devel mailing list).

src/mainx.c

@@ -250,6 +250,7 @@ int main(int argc, char *argv[], char *env[]) {
         REQUEST_ATOM(WM_CLIENT_LEADER);
         REQUEST_ATOM(_NET_CURRENT_DESKTOP);
         REQUEST_ATOM(_NET_ACTIVE_WINDOW);
+        REQUEST_ATOM(_NET_WORKAREA);
 
         /* TODO: this has to be more beautiful somewhen */
         int major, minor, error;
@@ -414,6 +415,7 @@ int main(int argc, char *argv[], char *env[]) {
         GET_ATOM(WM_CLIENT_LEADER);
         GET_ATOM(_NET_CURRENT_DESKTOP);
         GET_ATOM(_NET_ACTIVE_WINDOW);
+        GET_ATOM(_NET_WORKAREA);
 
         xcb_property_set_handler(&prophs, atoms[_NET_WM_WINDOW_TYPE], UINT_MAX, handle_window_type, NULL);
         /* TODO: In order to comply with EWMH, we have to watch _NET_WM_STRUT_PARTIAL */