Bug 747321 - Invite Attendees dialog: Free/busy display bug while scrolling with a 50% zoom. r=Mozilla

calendar/base/content/dialogs/calendar-event-dialog-freebusy.xml

@@ -603,7 +603,7 @@
       <property name="numHours">
         <getter><![CDATA[
           var numHours = this.mEndHour - this.mStartHour;
-          return Math.floor(numHours * 100 / this.mZoomFactor);
+          return Math.ceil(numHours * 100 / this.mZoomFactor);
         ]]></getter>
       </property>