[mutter] cogl: Add a slot for driver-private state to CoglContext

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit e03c75bac760ebd24036f8c7d009b3080c64743d
Author: Adam Jackson <ajax redhat com>
Date:   Thu Apr 9 13:06:28 2020 -0400

    cogl: Add a slot for driver-private state to CoglContext
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1194

 cogl/cogl/cogl-context-private.h           | 2 ++
 cogl/cogl/driver/gl/cogl-util-gl-private.h | 5 +++++
 cogl/cogl/driver/gl/cogl-util-gl.c         | 6 ++++++
 3 files changed, 13 insertions(+)
---
diff --git a/cogl/cogl/cogl-context-private.h b/cogl/cogl/cogl-context-private.h
index a2ed950d0c..594b80c301 100644
--- a/cogl/cogl/cogl-context-private.h
+++ b/cogl/cogl/cogl-context-private.h
@@ -73,6 +73,8 @@ struct _CoglContext
   const CoglDriverVtable *driver_vtable;
   const CoglTextureDriver *texture_driver;
 
+  void *driver_context;
+
   int glsl_major;
   int glsl_minor;
 
diff --git a/cogl/cogl/driver/gl/cogl-util-gl-private.h b/cogl/cogl/driver/gl/cogl-util-gl-private.h
index 369baab874..fb3f8534cc 100644
--- a/cogl/cogl/driver/gl/cogl-util-gl-private.h
+++ b/cogl/cogl/driver/gl/cogl-util-gl-private.h
@@ -76,6 +76,11 @@ _cogl_gl_error_to_string (GLenum error_code);
 
 #endif /* COGL_GL_DEBUG */
 
+typedef struct _CoglGLContext CoglGLContext; /* opaque for the moment */
+
+CoglGLContext *
+_cogl_driver_gl_context (CoglContext *context);
+
 gboolean
 _cogl_driver_gl_context_init (CoglContext *context);
 
diff --git a/cogl/cogl/driver/gl/cogl-util-gl.c b/cogl/cogl/driver/gl/cogl-util-gl.c
index 52ad54076f..afd6d3a8ad 100644
--- a/cogl/cogl/driver/gl/cogl-util-gl.c
+++ b/cogl/cogl/driver/gl/cogl-util-gl.c
@@ -75,6 +75,12 @@ _cogl_gl_error_to_string (GLenum error_code)
 }
 #endif /* COGL_GL_DEBUG */
 
+CoglGLContext *
+_cogl_driver_gl_context (CoglContext *context)
+{
+  return context->driver_context;
+}
+
 gboolean
 _cogl_driver_gl_context_init (CoglContext *context)
 {