compositor: init shell after xserver

This reverts a snip from commit d012e9df. On that commit, it was lost the
ability of calling X applications from desktop panel; xserver module
was setting DISPLAY only later, after panel was already launched.

Signed-off-by: Tiago Vignatti <tiago.vignatti@intel.com>

src/compositor.c

@@ -2601,9 +2601,6 @@ int main(int argc, char *argv[])
 	ec->option_idle_time = idle_time;
 	ec->idle_time = idle_time;
 
-	if (shell_init(ec) < 0)
-		exit(EXIT_FAILURE);
-
 	xserver_init = NULL;
 	if (xserver)
 		xserver_init = load_module("xserver-launcher.so",
@@ -2612,6 +2609,9 @@ int main(int argc, char *argv[])
 	if (xserver_init)
 		xserver_init(ec);
 
+	if (shell_init(ec) < 0)
+		exit(EXIT_FAILURE);
+
 	if (wl_display_add_socket(display, socket_name)) {
 		fprintf(stderr, "failed to add socket: %m\n");
 		exit(EXIT_FAILURE);