Fix memory leaks when using the new backends

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>

src/backend/xrender.c

@@ -461,6 +461,7 @@ static void deinit(void *backend_data, session_t *ps) {
 		xcb_render_free_picture(ps->c, xd->alpha_pict[i]);
 	xcb_render_free_picture(ps->c, xd->white_pixel);
 	xcb_render_free_picture(ps->c, xd->black_pixel);
+	free_conv(xd->shadow_kernel);
 	free(xd);
 }
 

src/compton.c

@@ -2934,6 +2934,14 @@ session_destroy(session_t *ps) {
     deinit_render(ps);
   }
 
+  // Free the damage ring
+  for (int i = 0; i < ps->ndamage; ++i) {
+    pixman_region32_fini(&ps->damage_ring[i]);
+  }
+  ps->ndamage = 0;
+  free(ps->damage_ring);
+  ps->damage_ring = ps->damage = NULL;
+
   // Flush all events
   x_sync(ps->c);
   ev_io_stop(ps->loop, &ps->xiow);

src/render.c

@@ -1211,13 +1211,6 @@ void deinit_render(session_t *ps) {
 	// Free other X resources
 	free_root_tile(ps);
 
-	// Free the damage ring
-	for (int i = 0; i < ps->ndamage; ++i)
-		pixman_region32_fini(&ps->damage_ring[i]);
-	ps->ndamage = 0;
-	free(ps->damage_ring);
-	ps->damage_ring = ps->damage = NULL;
-
 #ifdef CONFIG_OPENGL
 	free(ps->root_tile_paint.fbcfg);
 	glx_destroy(ps);