[gtk] rendernode: Don't use gdk_texture_download_surface

[Timm Bäder <baedert src gnome org>]

commit a9fec38680b7f223c2afc1cd7f5ca45d14414082
Author: Timm Bäder <mail baedert org>
Date:   Mon Mar 19 09:20:33 2018 +0100

    rendernode: Don't use gdk_texture_download_surface
    
    It can't handle the texture sizes we'd like to support

 gsk/gskrendernodeimpl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gsk/gskrendernodeimpl.c b/gsk/gskrendernodeimpl.c
index a34d7c05ab..5faf5ed950 100644
--- a/gsk/gskrendernodeimpl.c
+++ b/gsk/gskrendernodeimpl.c
@@ -702,7 +702,7 @@ gsk_texture_node_serialize (GskRenderNode *node)
   gsize stride;
 
   stride = 4 * self->texture->width;
-  data = g_malloc (sizeof (guchar) * stride * self->texture->width);
+  data = g_malloc (sizeof (guchar) * stride * self->texture->height);
   gdk_texture_download (self->texture, data, stride);
 
   result = g_variant_new ("(dddduu@au)",