Clear out expired aliens in Cocoa UI startup

TODO.FACTOR.txt

@@ -1,17 +1,15 @@
 should fix in 0.82:
 
+- 3 >n fep
 - amd64 %box-struct
 - get factor running on mac intel
 - when generating a 32-bit image on a 64-bit system, large numbers which should
   be bignums become fixnums
 - httpd fep
-- expired aliens in view hash
 - clicks sent twice
 - speed up ideas:
   - only do clipping for certain gadgets
   - use glRect
-- remove <char*>, <ushort*>, set-char*-nth, set-ushort*-nth since they
-  have incorrect semantics
 - cocoa: global menu bar with useful commands
 
 + portability:
@@ -58,6 +56,8 @@ should fix in 0.82:
 - core foundation should use unicode strings
 - alien>utf16-string, utf16-string>alien words
 - can <void*> only be called with an alien?
+- remove <char*>, <ushort*>, set-char*-nth, set-ushort*-nth since they
+  have incorrect semantics
 - improve callback efficiency
 - float intrinsics
 - complex float type

library/cocoa/ui.factor

@@ -3,11 +3,11 @@
 IN: objc-FactorView
 DEFER: FactorView
 
-USING: arrays cocoa errors freetype gadgets gadgets-launchpad
-gadgets-layouts gadgets-listener gadgets-panes hashtables kernel
-lists math namespaces objc objc-NSApplication objc-NSEvent
-objc-NSObject objc-NSOpenGLContext objc-NSOpenGLView objc-NSView
-objc-NSWindow sequences threads ;
+USING: alien arrays cocoa errors freetype gadgets
+gadgets-launchpad gadgets-layouts gadgets-listener gadgets-panes
+hashtables kernel lists math namespaces objc objc-NSApplication
+objc-NSEvent objc-NSObject objc-NSOpenGLContext
+objc-NSOpenGLView objc-NSView objc-NSWindow sequences threads ;
 
 ! Cocoa backend for Factor UI
 
@@ -18,6 +18,9 @@ SYMBOL: views
 
 H{ } clone views set-global
 
+: purge-expired ( hash -- hash )
+    [ drop expired? not ] hash-subset ;
+
 : view ( handle -- world ) views get hash ;
 
 : mouse-location ( view event -- loc )
@@ -189,6 +192,7 @@ IN: shells
     [
         [
             init-ui
+            purge-expired
             launchpad-window
             listener-window
             finish-launching