Drop the nograbs debug value

This was only used in the x11 backend, and I haven't seen it
actively recommended for debugging anything in ages.

docs/reference/gtk/running.md

@@ -211,9 +211,6 @@ are only available when GTK has been configured with `-Ddebug=true`.
 
 A number of options affect behavior instead of logging:
 
-`nograbs`
-: Turn off all pointer and keyboard grabs
-
 `portals`
 : Force the use of [portals](https://docs.flatpak.org/en/latest/portals.html)
 

gdk/gdk.c

@@ -120,7 +120,6 @@ static const GdkDebugKey gdk_debug_keys[] = {
   { "dmabuf",          GDK_DEBUG_DMABUF, "Information about dmabuf buffers" },
   { "offload",         GDK_DEBUG_OFFLOAD, "Information about subsurfaces and graphics offload" },
 
-  { "nograbs",         GDK_DEBUG_NOGRABS, "Disable pointer and keyboard grabs (X11)" },
   { "portals",         GDK_DEBUG_PORTALS, "Force use of portals" },
   { "no-portals",      GDK_DEBUG_NO_PORTALS, "Disable use of portals" },
   { "gl-disable",      GDK_DEBUG_GL_DISABLE, "Disable OpenGL support" },

gdk/gdkdebugprivate.h

@@ -40,7 +40,6 @@ typedef enum {
   GDK_DEBUG_OFFLOAD         = 1 << 12,
 
   /* flags below are influencing behavior */
-  GDK_DEBUG_NOGRABS         = 1 << 13,
   GDK_DEBUG_PORTALS         = 1 << 14,
   GDK_DEBUG_NO_PORTALS      = 1 << 15,
   GDK_DEBUG_GL_DISABLE      = 1 << 16,

gdk/x11/gdkdevice-xi2.c

@@ -333,9 +333,6 @@ gdk_x11_device_xi2_grab (GdkDevice    *device,
                                                         event_mask,
                                                         &mask.mask_len);
 
-  if (gdk_display_get_debug_flags (display) & GDK_DEBUG_NOGRABS)
-    status = GrabSuccess;
-  else
   status = XIGrabDevice (GDK_DISPLAY_XDISPLAY (display),
                          device_xi2->device_id,
                          xwindow,