gtkwindow: Revoke implicit grabs when activating an explicit one

Only if they fall outside the grab widget, in that case the widget holding
the implicit grab won't be receiving events anymore, so we can just undo
it.

gtk/gtkwindow.c

@@ -11470,6 +11470,34 @@ gtk_window_update_pointer_focus_on_state_change (GtkWindow *window,
     }
 }
 
+void
+gtk_window_maybe_revoke_implicit_grab (GtkWindow *window,
+                                       GdkDevice *device,
+                                       GtkWidget *grab_widget)
+{
+  GList *l = window->priv->foci, *cur;
+
+  while (l)
+    {
+      GtkPointerFocus *focus = l->data;
+
+      cur = l;
+      focus = cur->data;
+      l = cur->next;
+
+      if (focus->toplevel != window)
+        continue;
+
+      if (device && focus->device == device &&
+          focus->target != grab_widget &&
+          !gtk_widget_is_ancestor (focus->target, grab_widget))
+        gtk_window_set_pointer_focus_grab (window,
+                                           focus->device,
+                                           focus->sequence,
+                                           NULL);
+    }
+}
+
 void
 gtk_window_set_pointer_focus_grab (GtkWindow        *window,
                                    GdkDevice        *device,

gtk/gtkwindowgroup.c

@@ -253,6 +253,25 @@ gtk_window_group_get_current_grab (GtkWindowGroup *window_group)
   return NULL;
 }
 
+static void
+revoke_implicit_grabs (GtkWindowGroup *window_group,
+                       GdkDevice      *device,
+                       GtkWidget      *grab_widget)
+{
+  GList *windows, *l;
+
+  windows = gtk_window_group_list_windows (window_group);
+
+  for (l = windows; l; l = l->next)
+    {
+      gtk_window_maybe_revoke_implicit_grab (l->data,
+                                             device,
+                                             grab_widget);
+    }
+
+  g_list_free (windows);
+}
+
 void
 _gtk_window_group_add_grab (GtkWindowGroup *window_group,
                             GtkWidget      *widget)
@@ -261,6 +280,8 @@ _gtk_window_group_add_grab (GtkWindowGroup *window_group,
 
   priv = window_group->priv;
   priv->grabs = g_slist_prepend (priv->grabs, widget);
+
+  revoke_implicit_grabs (window_group, NULL, widget);
 }
 
 void
@@ -290,6 +311,8 @@ _gtk_window_group_add_device_grab (GtkWindowGroup *window_group,
   info->block_others = block_others;
 
   priv->device_grabs = g_slist_prepend (priv->device_grabs, info);
+
+  revoke_implicit_grabs (window_group, device, widget);
 }
 
 void

gtk/gtkwindowprivate.h

@@ -161,6 +161,10 @@ void             gtk_window_set_pointer_focus_grab (GtkWindow        *window,
 void             gtk_window_update_pointer_focus_on_state_change (GtkWindow *window,
                                                                   GtkWidget *widget);
 
+void             gtk_window_maybe_revoke_implicit_grab (GtkWindow *window,
+                                                        GdkDevice *device,
+                                                        GtkWidget *grab_widget);
+
 G_END_DECLS
 
 #endif /* __GTK_WINDOW_PRIVATE_H__ */