[metacity] display: remove benign warning for older X clients

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 4c8927e5c11a9bc7aed40b18dda6961be64e36cc
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sun Aug 18 16:11:56 2019 +0300

    display: remove benign warning for older X clients
    
    The default configuration of libinput-gestures utility invokes wmctrl to
    switch between desktops. It uses wmctrl because this works on both Xorg
    and Wayland (via XWayland). Unfortunately, this generates the following
    warning message every time, in both Xorg and Wayland desktops:
    
    "Received a NET_CURRENT_DESKTOP message from a broken (outdated) client
    who sent a 0 timestamp"
    
    The desktop switch still works fine. The tiny code change here removes
    this specific warning because, as the prefacing code comment originally
    said and still says, older clients can validly pass a 0 time value so
    why complain about that?
    
    I also refactored the "if (workspace)" code slightly to avoid the double
    test of the workspace value.
    
    Based on mutter commit:
    https://gitlab.gnome.org/GNOME/mutter/commit/e9cc220c8e0fd6843d2e77

 src/core/display.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)
---
diff --git a/src/core/display.c b/src/core/display.c
index 57029807..ce3b6904 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -2440,19 +2440,18 @@ event_callback (XEvent   *event,
 
                   workspace = meta_screen_get_workspace_by_index (screen, space);
 
-                  /* Handle clients using the older version of the spec... */
-                  if (time == 0 && workspace)
+                  if (workspace)
                     {
-                      g_warning ("Received a NET_CURRENT_DESKTOP message from "
-                                 "a broken (outdated) client who sent a 0 timestamp");
+                      /* Handle clients using the older version of the spec... */
+                      if (time == 0)
+                        time = meta_display_get_current_time_roundtrip (display);
 
-                      time = meta_display_get_current_time_roundtrip (display);
+                      meta_workspace_activate (workspace, time);
                     }
-
-                  if (workspace)
-                    meta_workspace_activate (workspace, time);
                   else
-                    meta_verbose ("Don't know about workspace %d\n", space);
+                    {
+                      meta_verbose ("Don't know about workspace %d\n", space);
+                    }
                 }
               else if (event->xclient.message_type ==
                        display->atom__NET_NUMBER_OF_DESKTOPS)