[geary/geary-0.12] Fix reference tracking logs not being output when enabled.

[Michael Gratton <mjog src gnome org>]

commit 28fff8fb1714b947374f67dc471ec65136962d05
Author: Michael James Gratton <mike vee net>
Date:   Wed Feb 21 11:27:52 2018 +1100

    Fix reference tracking logs not being output when enabled.
    
    * src/client/application/geary-application.vala (Application): Use
      Application.quit to exit normally rather Gtk.main_quit so that control
      is returned to the main() entry-point.

 src/client/application/geary-application.vala |   13 ++++---------
 1 files changed, 4 insertions(+), 9 deletions(-)
---
diff --git a/src/client/application/geary-application.vala b/src/client/application/geary-application.vala
index cc326cb..fecacf6 100644
--- a/src/client/application/geary-application.vala
+++ b/src/client/application/geary-application.vala
@@ -419,19 +419,14 @@ public class GearyApplication : Gtk.Application {
             int64 delta_usec = get_monotonic_time() - start_usec;
             if (delta_usec >= FORCE_SHUTDOWN_USEC) {
                 debug("Forcing shutdown of Geary, %ss passed...", (delta_usec / USEC_PER_SEC).to_string());
-                
-                break;
+                Posix.exit(2);
             }
         }
-        
-        if (Gtk.main_level() > 0)
-            Gtk.main_quit();
-        else
-            Posix.exit(exitcode);
-        
+
+        quit();
         Date.terminate();
     }
-    
+
     /**
      * A callback for GearyApplication.exiting should return cancel_exit() to prevent the
      * application from exiting.