Gtk+ 3: open library in "global" mode to support the printer dialog

Opening a shared object in global mode risks conflicts with
other shared objects, but opening only one library that way
will hopefully not create conflicts.

(cherry picked from commit b29a7ae399)

gui-doc/scribblings/framework/notify.scrbl

@@ -42,6 +42,8 @@ listeners when the contents of the cell is changed.
 @defmethod[(remove-all-listeners) void?]{
   Removes all previously registered callbacks.
 }
+
+@history[#:added "1.18"]{}
 }
 
 @defproc[(notify:notify-box/pref
@@ -67,6 +69,8 @@ reflected in the notify-box.
 (send nb set 'deer)
 (animal)
 ]
+
+@history[#:added "1.18"]{}
 }
 
 @defform[(notify:define-notify name value-expr)
@@ -97,6 +101,8 @@ Useful for aggregating many notify-boxes together into one
   (send food set 'honey))
 (send c get-animal)
 ]
+
+@history[#:added "1.18"]{}
 }
 
 @defproc[(notify:menu-option/notify-box
@@ -108,6 +114,8 @@ Useful for aggregating many notify-boxes together into one
 Creates a @racket[checkable-menu-item%] tied to @racket[notify-box]. The menu item is
 checked whenever @racket[(send notify-box get)] is true. Clicking the
 menu item toggles the value of @racket[notify-box] and invokes its listeners.
+
+@history[#:added "1.18"]{}
 }
 
 @defproc[(notify:check-box/notify-box
@@ -121,6 +129,8 @@ Creates a @racket[check-box%] tied to @racket[notify-box]. The
 check-box is checked whenever @racket[(send notify-box get)] is
 true. Clicking the check box toggles the value of @racket[notify-box]
 and invokes its listeners.
+
+@history[#:added "1.18"]{}
 }
 
 @defproc[(notify:choice/notify-box
@@ -138,6 +148,8 @@ its listeners.
 
 If the value of @racket[notify-box] is not in @racket[choices], either
 initially or upon an update, an error is raised.
+
+@history[#:added "1.18"]{}
 }
 
 @defproc[(notify:menu-group/notify-box
@@ -151,6 +163,8 @@ Returns a list of @racket[checkable-menu-item%] controls tied to
 @racket[(send notify-box get)]. Clicking a menu item updates
 @racket[notify-box] to its label and invokes @racket[notify-box]'s
 listeners.
+
+@history[#:added "1.18"]{}
 }
 
 

gui-lib/framework/preferences.rkt

@@ -389,7 +389,9 @@ the state transitions / contracts are:
   (pref)
   @{Returns a procedure that when applied to zero arguments retrieves the
     current value of the preference named @racket[pref] and when
-    applied to one argument updates the preference named @racket[pref].})
+    applied to one argument updates the preference named @racket[pref].
+
+    @history[#:added "1.18"]{}})
  
  (proc-doc/names
   preferences:add-callback

gui-lib/mred/private/wx/cocoa/frame.rkt

@@ -429,7 +429,8 @@
       (when (zero? flush-disabled)
         (tellv cocoa enableFlushWindow)
         (when (version-10.11-or-later?)
-          (tellv cocoa setAutodisplay: #:type _BOOL #t))))
+          (tellv cocoa setAutodisplay: #:type _BOOL #t)
+          (tellv cocoa displayIfNeeded))))
 
     (define/public (force-window-focus)
       (let ([next (get-app-front-window)])

gui-lib/mred/private/wx/gtk/gtk3.rkt

@@ -8,7 +8,9 @@
 (define (get-gdk3-lib)
   (ffi-lib "libgdk-3" '("0" "") #:fail (lambda () #f)))
 (define (get-gtk3-lib)
-  (ffi-lib "libgtk-3" '("0" "") #:fail (lambda () #f)))
+  ;; Open in "global" mode so that gtk_print_operation_run()
+  ;; can find the printer dialog using _g_module_symbol():
+  (ffi-lib "libgtk-3" '("0" "") #:global? #t #:fail (lambda () #f)))
 
 (define gtk3?
   (and (not (getenv "PLT_GTK2"))