[sysprof] window: add each instance to each own group

[Christian Hergert <chergert src gnome org>]

commit 987f66197f0fd69febd71c0ce095fcf2920bbf28
Author: Dimitrios Christidis <dimitrios christidis me>
Date:   Sat Apr 8 14:33:31 2017 +0200

    window: add each instance to each own group
    
    Prevents the About dialog from blocking interactions on all windows.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=781053

 src/sp-window.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/src/sp-window.c b/src/sp-window.c
index 9e1569f..2084426 100644
--- a/src/sp-window.c
+++ b/src/sp-window.c
@@ -841,6 +841,7 @@ sp_window_init (SpWindow *self)
     { "screenshot",  sp_window_screenshot },
   };
   SpSelection *selection;
+  g_autoptr(GtkWindowGroup) window_group = NULL;
 
   gtk_widget_init_template (GTK_WIDGET (self));
 
@@ -901,6 +902,12 @@ sp_window_init (SpWindow *self)
    * launch, enter, escape, view.
    */
   gtk_window_set_focus (GTK_WINDOW (self), GTK_WIDGET (self->record_button));
+
+  /*
+   * Prevent grabs (e.g. modal dialogs) from affecting multiple windows.
+   */
+  window_group = gtk_window_group_new ();
+  gtk_window_group_add_window (window_group, GTK_WINDOW (self));
 }
 
 static void