[gtk+] gsk: Check for NULL in calls to gsk_cairo_node_get_surface()

[Benjamin Otte <otte src gnome org>]

commit 3ef03c8bc0bed418406418127061ffc489aa938e
Author: Benjamin Otte <otte redhat com>
Date:   Thu Dec 15 10:08:46 2016 +0100

    gsk: Check for NULL in calls to gsk_cairo_node_get_surface()
    
    That function does actually sometimes return NULL and is documented to
    do so, so handle that case in the renderers (by omitting the node).

 gsk/gskglrenderer.c       |    3 +++
 gsk/gskvulkanrenderpass.c |    9 ++++++---
 2 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/gsk/gskglrenderer.c b/gsk/gskglrenderer.c
index 1c09244..09a63ed 100644
--- a/gsk/gskglrenderer.c
+++ b/gsk/gskglrenderer.c
@@ -713,6 +713,9 @@ gsk_gl_renderer_add_render_item (GskGLRenderer           *self,
         cairo_surface_t *surface = gsk_cairo_node_get_surface (node);
         int gl_min_filter = GL_NEAREST, gl_mag_filter = GL_NEAREST;
 
+        if (surface == NULL)
+          return;
+
         get_gl_scaling_filters (node, &gl_min_filter, &gl_mag_filter);
 
         /* Upload the Cairo surface to a GL texture */
diff --git a/gsk/gskvulkanrenderpass.c b/gsk/gskvulkanrenderpass.c
index a2d66c8..81912dd 100644
--- a/gsk/gskvulkanrenderpass.c
+++ b/gsk/gskvulkanrenderpass.c
@@ -100,9 +100,12 @@ gsk_vulkan_render_pass_add_node (GskVulkanRenderPass           *self,
       break;
 
     case GSK_CAIRO_NODE:
-      op.type = GSK_VULKAN_OP_SURFACE;
-      op.render.pipeline = gsk_vulkan_render_get_pipeline (render, GSK_VULKAN_PIPELINE_BLIT);
-      g_array_append_val (self->render_ops, op);
+      if (gsk_cairo_node_get_surface (node) != NULL)
+        {
+          op.type = GSK_VULKAN_OP_SURFACE;
+          op.render.pipeline = gsk_vulkan_render_get_pipeline (render, GSK_VULKAN_PIPELINE_BLIT);
+          g_array_append_val (self->render_ops, op);
+        }
       break;
 
     case GSK_TEXTURE_NODE: