make app update window on Mac big enough to fit everything. b=307436 r=mano sr=ben

toolkit/locales/en-US/chrome/mozapps/update/updates.dtd

@@ -1,5 +1,8 @@
 <!ENTITY  updateWizard.title              "Software Update">
 
+<!ENTITY  window.width                    "36em">
+<!ENTITY  window.macWidth                 "39em">
+
 <!ENTITY  checking.title                  "Checking for Updates">
 <!ENTITY  checking.label                  "&brandShortName; is now checking for updates...">
 

toolkit/mozapps/update/content/updates.xul

@@ -52,7 +52,11 @@
         xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
         title="&updateWizard.title;" 
         label="" description=""
-        windowtype="Update:Wizard" style="width: 36em;"
+#ifdef XP_MACOSX
+        windowtype="Update:Wizard" style="width: &window.macWidth;;"
+#else
+        windowtype="Update:Wizard" style="width: &window.width;;"
+#endif
         onwizardfinish="gUpdates.onWizardFinish();"
         onwizardcancel="gUpdates.onWizardCancel();"
         onwizardnext="gUpdates.onWizardNext();"