gl-renderer: Call glViewport after the context is made current

Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>

src/gl-renderer.c

@@ -945,15 +945,15 @@ gl_renderer_repaint_output(struct weston_output *output,
 	pixman_region32_t buffer_damage, total_damage;
 	enum gl_border_status border_damage = BORDER_STATUS_CLEAN;
 
+	if (use_output(output) < 0)
+		return;
+
 	/* Calculate the viewport */
 	glViewport(go->borders[GL_RENDERER_BORDER_LEFT].width,
 		   go->borders[GL_RENDERER_BORDER_BOTTOM].height,
 		   output->current_mode->width,
 		   output->current_mode->height);
 
-	if (use_output(output) < 0)
-		return;
-
 	/* if debugging, redraw everything outside the damage to clean up
 	 * debug lines from the previous draw on this buffer:
 	 */