[gtk] gl renderer: Don't upload GL textures into the icon cache

[Timm Bäder <baedert src gnome org>]

commit 071748592d30756400f9e047e4c5fcfe6add02e6
Author: Timm Bäder <mail baedert org>
Date:   Sat Jun 29 07:13:10 2019 +0200

    gl renderer: Don't upload GL textures into the icon cache

 gsk/gl/gskglrenderer.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/gsk/gl/gskglrenderer.c b/gsk/gl/gskglrenderer.c
index 9a3bd13e76..0597785929 100644
--- a/gsk/gl/gskglrenderer.c
+++ b/gsk/gl/gskglrenderer.c
@@ -808,7 +808,8 @@ upload_texture (GskGLRenderer *self,
   int texture_id;
 
   if (texture->width <= 128 &&
-      texture->height <= 128)
+      texture->height <= 128 &&
+      !GDK_IS_GL_TEXTURE (texture))
     {
       graphene_rect_t trect;