[gnome-shell/gnome-3-10] shell-app: Track changes to MetaWindow:skip-taskbar

[Florian Müllner <fmuellner src gnome org>]

commit c5c3dd0997b22706940985c2bb7461ce8a8ff1dd
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Jan 30 17:33:36 2014 +0100

    shell-app: Track changes to MetaWindow:skip-taskbar
    
    So far we have assumed that whether or not a window is interesting
    is static. In general this is the case, but as it is legal for the
    underlying properties to change at any time, there are of course
    offenders that actually do this (flash I'm looking at ya).
    While we used the property to determine whether a window should be
    tracked or not, the worst case was showing windows that should be
    hidden or missing windows that should be shown.
    However as we nowadays base an app's running state on the number of
    interesting windows, we need to be more careful in order to avoid
    ending up with running apps with no windows.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=723308

 src/shell-app.c |   42 +++++++++++++++++++++++++++++++++++-------
 1 files changed, 35 insertions(+), 7 deletions(-)
---
diff --git a/src/shell-app.c b/src/shell-app.c
index 30ea6b8..99f51ed 100644
--- a/src/shell-app.c
+++ b/src/shell-app.c
@@ -931,6 +931,37 @@ shell_app_on_user_time_changed (MetaWindow *window,
 }
 
 static void
+shell_app_sync_running_state (ShellApp *app)
+{
+  g_return_if_fail (app->running_state != NULL);
+
+  if (app->running_state->interesting_windows == 0)
+    shell_app_state_transition (app, SHELL_APP_STATE_STOPPED);
+  else if (app->state != SHELL_APP_STATE_STARTING)
+    shell_app_state_transition (app, SHELL_APP_STATE_RUNNING);
+}
+
+
+static void
+shell_app_on_skip_taskbar_changed (MetaWindow *window,
+                                   GParamSpec *pspec,
+                                   ShellApp   *app)
+{
+  g_assert (app->running_state != NULL);
+
+  /* we rely on MetaWindow:skip-taskbar only being notified
+   * when it actually changes; when that assumption breaks,
+   * we'll have to track the "interesting" windows themselves
+   */
+  if (meta_window_is_skip_taskbar (window))
+    app->running_state->interesting_windows--;
+  else
+    app->running_state->interesting_windows++;
+
+  shell_app_sync_running_state (app);
+}
+
+static void
 shell_app_on_ws_switch (MetaScreen         *screen,
                         int                 from,
                         int                 to,
@@ -1026,16 +1057,14 @@ _shell_app_add_window (ShellApp        *app,
   app->running_state->windows = g_slist_prepend (app->running_state->windows, g_object_ref (window));
   g_signal_connect (window, "unmanaged", G_CALLBACK(shell_app_on_unmanaged), app);
   g_signal_connect (window, "notify::user-time", G_CALLBACK(shell_app_on_user_time_changed), app);
+  g_signal_connect (window, "notify::skip-taskbar", G_CALLBACK(shell_app_on_skip_taskbar_changed), app);
 
   shell_app_update_app_menu (app, window);
   shell_app_ensure_busy_watch (app);
 
   if (shell_window_tracker_is_window_interesting (window))
     app->running_state->interesting_windows++;
-
-  if (app->state != SHELL_APP_STATE_STARTING &&
-      app->running_state->interesting_windows > 0)
-    shell_app_state_transition (app, SHELL_APP_STATE_RUNNING);
+  shell_app_sync_running_state (app);
 
   g_object_thaw_notify (G_OBJECT (app));
 
@@ -1053,14 +1082,13 @@ _shell_app_remove_window (ShellApp   *app,
 
   g_signal_handlers_disconnect_by_func (window, G_CALLBACK(shell_app_on_unmanaged), app);
   g_signal_handlers_disconnect_by_func (window, G_CALLBACK(shell_app_on_user_time_changed), app);
+  g_signal_handlers_disconnect_by_func (window, G_CALLBACK(shell_app_on_skip_taskbar_changed), app);
   g_object_unref (window);
   app->running_state->windows = g_slist_remove (app->running_state->windows, window);
 
   if (shell_window_tracker_is_window_interesting (window))
     app->running_state->interesting_windows--;
-
-  if (app->running_state->interesting_windows == 0)
-    shell_app_state_transition (app, SHELL_APP_STATE_STOPPED);
+  shell_app_sync_running_state (app);
 
   if (app->running_state && app->running_state->windows == NULL)
     g_clear_pointer (&app->running_state, unref_running_state);