Use explicit style for collapsing calendar views, rather than relying on XUL

property propagation and re-cascade.  (Sounds obvious when I write it like
that, doesn't it?)  Also, restore the setTimeout scheduling of the calendar
showing, so that we don't end up with singularity-sized event boxes the first
time. r=chase-is-a-god-among-men.

calendar/lightning/content/messenger-overlay-sidebar.css

@@ -0,0 +1,3 @@
+#calendar-view-box {
+    visibility: collapse;
+}

calendar/lightning/content/messenger-overlay-sidebar.js

@@ -142,8 +142,8 @@ function selectedCalendarPane(event)
 
     // give the view the calendar, but make sure that everything
     // has uncollapsed first before we try to relayout!
-    showCalendar(today());
-    //setTimeout(function() { showCalendar(today()); }, 0);
+    // showCalendar(today());
+    setTimeout(function() { showCalendar(today()); }, 0);
 }
 
 function LtnObserveDisplayDeckChange(event)
@@ -155,11 +155,9 @@ function LtnObserveDisplayDeckChange(event)
         GetMessagePane().collapsed = true;
         document.getElementById("threadpane-splitter").collapsed = true;
         gSearchBox.collapsed = true;
-        document.getElementById("calendar-view-box").collapsed = false;
+        deck.selectedPanel.style.visibility = "";
     } else {
-        document.getElementById("calendar-view-box").collapsed = true;
-        // Later: mark the view as not needing reflow due to new events coming
-        // in, for better performance and batching.
+        document.getElementById("calendar-view-box").style.visibility = "collapse";
     }
 }
 

calendar/lightning/content/messenger-overlay-sidebar.xul

@@ -68,7 +68,7 @@
 </vbox>
 
 <deck id="displayDeck">
-  <deck flex="1" collapsed="true" id="calendar-view-box">
+  <deck flex="1" id="calendar-view-box">
     <calendar-month-view id="calendar-month-view" flex="1"/>
     <calendar-multiday-view orient="vertical" id="calendar-multiday-view" flex="1"/>
   </deck>

calendar/lightning/jar.mn

@@ -2,6 +2,7 @@ lightning.jar:
   content/lightning/lightning-utils.js			(content/lightning-utils.js) 
   content/lightning/messenger-overlay-sidebar.xul	(content/messenger-overlay-sidebar.xul)
   content/lightning/messenger-overlay-sidebar.js	(content/messenger-overlay-sidebar.js)
+  content/lightning/messenger-overlay-sidebar.css	(content/messenger-overlay-sidebar.css)
   content/lightning/calendar-management.js		(content/calendar-management.js)
   content/lightning/lightning-widgets.css		(content/lightning-widgets.css)
   content/lightning/agenda-tree-overlay.xul             (content/agenda-tree-overlay.xul)