[gtk+] quartz: fix a race condition when waking up the CGRunLoop

[Michael Natterer <mitch src gnome org>]

commit e19cbd7a045935a63801bc853746b5225d7de426
Author: Michael Natterer <mitch gimp org>
Date:   Fri Nov 11 23:49:21 2011 +0100

    quartz: fix a race condition when waking up the CGRunLoop
    
    Wake up the run loop unconditionally (don't check if it is waiting) because
    it might go into waiting state right after we checked for it. Fixes GIMP
    startup (which has a lot of GIOChannel I/O but zero NSEvents) from several
    minutes to a few seconds.
    (cherry picked from commit 0729cdc9a1e8003c41d3ebf20eecfe2d1b29ffbe)

 gdk/quartz/gdkeventloop-quartz.c |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)
---
diff --git a/gdk/quartz/gdkeventloop-quartz.c b/gdk/quartz/gdkeventloop-quartz.c
index 702238c..4181a5d 100644
--- a/gdk/quartz/gdkeventloop-quartz.c
+++ b/gdk/quartz/gdkeventloop-quartz.c
@@ -207,9 +207,12 @@ signal_main_thread (void)
    */
   if (!run_loop_polling_async)
     CFRunLoopSourceSignal (select_main_thread_source);
-  
-  if (CFRunLoopIsWaiting (main_thread_run_loop))
-    CFRunLoopWakeUp (main_thread_run_loop);
+
+  /* Don't check for CFRunLoopIsWaiting() here because it causes a
+   * race condition (the loop could go into waiting state right after
+   * we checked).
+   */
+  CFRunLoopWakeUp (main_thread_run_loop);
 }
 
 static void *