[epiphany] Close window after drag/drop last tab to another window

[Michael Catanzaro <mcatanzaro src gnome org>]

commit a4ee4eb32dbaee4c117afd0198f4496581604a18
Author: Jan-Michael Brummer <jan brummer tabos org>
Date:   Wed Apr 17 20:53:09 2019 +0200

    Close window after drag/drop last tab to another window
    
    Fixes: https://gitlab.gnome.org/GNOME/epiphany/issues/731

 src/ephy-window.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/src/ephy-window.c b/src/ephy-window.c
index f5934d752..e4c137930 100644
--- a/src/ephy-window.c
+++ b/src/ephy-window.c
@@ -2707,6 +2707,9 @@ notebook_page_removed_cb (EphyNotebook *notebook,
     (ephy_embed_get_web_view (embed), G_CALLBACK (download_only_load_cb), window);
 
   tab_accels_update (window);
+
+  if (gtk_notebook_get_n_pages (window->notebook) == 0)
+    ephy_window_close (window);
 }
 
 static void