[mutter] Remove unused flag COGL_WINSYS_FEATURE_SWAP_THROTTLE

[Jonas Ådahl <jadahl src gnome org>]

commit f3ad63e2068d79fb3ed3a990751064efe7b92ab8
Author: Daniel van Vugt <daniel van vugt canonical com>
Date:   Fri Jul 31 16:12:28 2020 +0800

    Remove unused flag COGL_WINSYS_FEATURE_SWAP_THROTTLE
    
    This also removes an old comment about `wait_for_pending_flips` which
    no longer exists.
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1390

 cogl/cogl/cogl-types.h                               | 4 ----
 cogl/cogl/winsys/cogl-winsys-glx-feature-functions.h | 2 +-
 src/backends/native/meta-renderer-native.c           | 7 -------
 3 files changed, 1 insertion(+), 12 deletions(-)
---
diff --git a/cogl/cogl/cogl-types.h b/cogl/cogl/cogl-types.h
index 495070e9de..751a84d1d9 100644
--- a/cogl/cogl/cogl-types.h
+++ b/cogl/cogl/cogl-types.h
@@ -428,10 +428,6 @@ typedef enum _CoglWinsysFeature
    * framebuffers at the same time. */
   COGL_WINSYS_FEATURE_MULTIPLE_ONSCREEN,
 
-  /* Available if onscreen framebuffer swaps can be automatically
-   * throttled to the vblank frequency. */
-  COGL_WINSYS_FEATURE_SWAP_THROTTLE,
-
   /* 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-glx-feature-functions.h 
b/cogl/cogl/winsys/cogl-winsys-glx-feature-functions.h
index ed9df707f5..e6be46502c 100644
--- a/cogl/cogl/winsys/cogl-winsys-glx-feature-functions.h
+++ b/cogl/cogl/winsys/cogl-winsys-glx-feature-functions.h
@@ -130,7 +130,7 @@ COGL_WINSYS_FEATURE_BEGIN (255, 255,
                            "SGI\0",
                            "swap_control\0",
                            0,
-                           COGL_WINSYS_FEATURE_SWAP_THROTTLE)
+                           0)
 COGL_WINSYS_FEATURE_FUNCTION (int, glXSwapInterval,
                               (int interval))
 COGL_WINSYS_FEATURE_END ()
diff --git a/src/backends/native/meta-renderer-native.c b/src/backends/native/meta-renderer-native.c
index f3a6bd7e45..ffc6791a30 100644
--- a/src/backends/native/meta-renderer-native.c
+++ b/src/backends/native/meta-renderer-native.c
@@ -2200,13 +2200,6 @@ meta_renderer_native_init_egl_context (CoglContext *cogl_context,
                   COGL_WINSYS_FEATURE_MULTIPLE_ONSCREEN,
                   TRUE);
 
-  /* COGL_WINSYS_FEATURE_SWAP_THROTTLE is always true for this renderer
-   * because we have the call to wait_for_pending_flips on every frame.
-   */
-  COGL_FLAGS_SET (cogl_context->winsys_features,
-                  COGL_WINSYS_FEATURE_SWAP_THROTTLE,
-                  TRUE);
-
 #ifdef HAVE_EGL_DEVICE
   if (renderer_gpu_data->mode == META_RENDERER_NATIVE_MODE_EGL_DEVICE)
     COGL_FLAGS_SET (cogl_context->features,