[libadwaita/wip/exalm/tab-middle-click] tab-box: Claim the sequence on press for middle click

[Alexander Mikhaylenko <alexm src gnome org>]

commit 50db2aa22d3dfc1afc2b3f6e90758305865c8b20
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Sun May 1 21:58:50 2022 +0400

    tab-box: Claim the sequence on press for middle click
    
    Make it work with window handles.
    
    Fixes https://gitlab.gnome.org/GNOME/libadwaita/-/issues/471

 src/adw-tab-box.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/src/adw-tab-box.c b/src/adw-tab-box.c
index 68340912..48286a7c 100644
--- a/src/adw-tab-box.c
+++ b/src/adw-tab-box.c
@@ -2917,8 +2917,11 @@ pressed_cb (AdwTabBox  *self,
 
   button = gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture));
 
-  if (button == GDK_BUTTON_MIDDLE)
+  if (button == GDK_BUTTON_MIDDLE) {
+    gtk_gesture_set_state (gesture, GTK_EVENT_SEQUENCE_CLAIMED);
+
     return;
+  }
 
   if (button != GDK_BUTTON_PRIMARY) {
     gtk_gesture_set_state (gesture, GTK_EVENT_SEQUENCE_DENIED);
@@ -2958,7 +2961,6 @@ released_cb (AdwTabBox  *self,
   button = gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture));
 
   if (button == GDK_BUTTON_MIDDLE) {
-    gtk_gesture_set_state (gesture, GTK_EVENT_SEQUENCE_CLAIMED);
     adw_tab_view_close_page (self->view, info->page);
 
     return;