[mutter] wayland-buffer: Create EGLStream texture at buffer_realize time

[Jonas Ådahl <jadahl src gnome org>]

commit edd3634bb52a8efc687c612152fda5c996e94d26
Author: Miguel A. Vico <mvicomoya nvidia com>
Date:   Fri May 5 18:23:57 2017 -0700

    wayland-buffer: Create EGLStream texture at buffer_realize time
    
    When dealing with synchronized subsurfaces, we defer buffer attachments
    until the parent surface state is applied.
    
    That causes interaction issues with EGLStream backed buffers, as the
    client expects the compositor-side stream to be functional after it
    requests a wl_surface::attach.
    
    By allowing the compositor to realize buffers without attaching them, we
    could resolve the issue above if we define a realized EGLStream buffer
    as a functional EGLStream (EGLStream + attached consumer).
    
    This change moves the texture consumer creation part from the attach
    function to the realize one.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=782575

 src/wayland/meta-wayland-buffer.c | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)
---
diff --git a/src/wayland/meta-wayland-buffer.c b/src/wayland/meta-wayland-buffer.c
index c759eefc1..3396f450c 100644
--- a/src/wayland/meta-wayland-buffer.c
+++ b/src/wayland/meta-wayland-buffer.c
@@ -129,8 +129,18 @@ meta_wayland_buffer_realize (MetaWaylandBuffer *buffer)
   stream = meta_wayland_egl_stream_new (buffer, NULL);
   if (stream)
     {
+      CoglTexture2D *texture;
+
       buffer->egl_stream.stream = stream;
       buffer->type = META_WAYLAND_BUFFER_TYPE_EGL_STREAM;
+
+      texture = meta_wayland_egl_stream_create_texture (stream, NULL);
+      if (!texture)
+        return FALSE;
+
+      buffer->texture = COGL_TEXTURE (texture);
+      buffer->is_y_inverted = meta_wayland_egl_stream_is_y_inverted (stream);
+
       return TRUE;
     }
 
@@ -320,18 +330,6 @@ egl_stream_buffer_attach (MetaWaylandBuffer  *buffer,
 
   g_assert (stream);
 
-  if (!buffer->texture)
-    {
-      CoglTexture2D *texture;
-
-      texture = meta_wayland_egl_stream_create_texture (stream, error);
-      if (!texture)
-        return FALSE;
-
-      buffer->texture = COGL_TEXTURE (texture);
-      buffer->is_y_inverted = meta_wayland_egl_stream_is_y_inverted (stream);
-    }
-
   if (!meta_wayland_egl_stream_attach (stream, error))
     return FALSE;