[mutter] cogl/winsys: Remove 'multiple-onscreen' feature

[Marge Bot <marge-bot src gnome org>]

commit 259a906b8cd0a126af4a7d707cea3b142d1e623a
Author: Jonas Ådahl <jadahl gmail com>
Date:   Fri Sep 17 11:46:24 2021 +0200

    cogl/winsys: Remove 'multiple-onscreen' feature
    
    It was always set, and is no longer used; remove it.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2002>

 cogl/cogl/cogl-types.h                     | 4 ----
 cogl/cogl/winsys/cogl-winsys-egl-x11.c     | 4 ----
 cogl/cogl/winsys/cogl-winsys-glx.c         | 5 -----
 src/backends/native/meta-renderer-native.c | 3 ---
 4 files changed, 16 deletions(-)
---
diff --git a/cogl/cogl/cogl-types.h b/cogl/cogl/cogl-types.h
index cd92b2ecd3..c55ad1f4cd 100644
--- a/cogl/cogl/cogl-types.h
+++ b/cogl/cogl/cogl-types.h
@@ -423,10 +423,6 @@ typedef enum _CoglFilterReturn { /*< prefix=COGL_FILTER >*/
 
 typedef enum _CoglWinsysFeature
 {
-  /* Available if the window system can support multiple onscreen
-   * framebuffers at the same time. */
-  COGL_WINSYS_FEATURE_MULTIPLE_ONSCREEN,
-
   /* Available if its possible to query a counter that
    * increments at each vblank. */
   COGL_WINSYS_FEATURE_VBLANK_COUNTER,
diff --git a/cogl/cogl/winsys/cogl-winsys-egl-x11.c b/cogl/cogl/winsys/cogl-winsys-egl-x11.c
index 2c8141fae8..abe740a210 100644
--- a/cogl/cogl/winsys/cogl-winsys-egl-x11.c
+++ b/cogl/cogl/winsys/cogl-winsys-egl-x11.c
@@ -325,10 +325,6 @@ _cogl_winsys_egl_context_init (CoglContext *context,
                                  event_filter_cb,
                                  context);
 
-  COGL_FLAGS_SET (context->winsys_features,
-                  COGL_WINSYS_FEATURE_MULTIPLE_ONSCREEN,
-                  TRUE);
-
   /* We'll manually handle queueing dirty events in response to
    * Expose events from X */
   COGL_FLAGS_SET (context->private_features,
diff --git a/cogl/cogl/winsys/cogl-winsys-glx.c b/cogl/cogl/winsys/cogl-winsys-glx.c
index f3738e07c0..f3230ef5d4 100644
--- a/cogl/cogl/winsys/cogl-winsys-glx.c
+++ b/cogl/cogl/winsys/cogl-winsys-glx.c
@@ -379,11 +379,6 @@ update_base_winsys_features (CoglRenderer *renderer)
                   COGL_WINSYS_FEATURE_VBLANK_COUNTER,
                   FALSE);
 
-
-  COGL_FLAGS_SET (glx_renderer->base_winsys_features,
-                  COGL_WINSYS_FEATURE_MULTIPLE_ONSCREEN,
-                  TRUE);
-
   /* Because of the direct-context dependency, the VBLANK_WAIT feature
    * doesn't reflect the presence of GLX_SGI_video_sync.
    */
diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
index bc378fb199..e1f6e08523 100644
--- a/src/backends/native/meta-renderer-native.c
+++ b/src/backends/native/meta-renderer-native.c
@@ -866,9 +866,6 @@ meta_renderer_native_init_egl_context (CoglContext *cogl_context,
   COGL_FLAGS_SET (cogl_context->winsys_features,
                   COGL_WINSYS_FEATURE_SYNC_AND_COMPLETE_EVENT,
                   TRUE);
-  COGL_FLAGS_SET (cogl_context->winsys_features,
-                  COGL_WINSYS_FEATURE_MULTIPLE_ONSCREEN,
-                  TRUE);
 
 #ifdef HAVE_EGL_DEVICE
   if (renderer_gpu_data->mode == META_RENDERER_NATIVE_MODE_EGL_DEVICE)