Datepicker: Set font-size to 0em on ui-datepicker-row-break to override font-size coming from ui-widget which caused the height to be too tall in IE

(cherry picked from commit abf8330)

Author: kborchers

themes/base/jquery.ui.datepicker.css

@@ -39,7 +39,7 @@
 .ui-datepicker-multi .ui-datepicker-group-last .ui-datepicker-header { border-left-width:0; }
 .ui-datepicker-multi .ui-datepicker-group-middle .ui-datepicker-header { border-left-width:0; }
 .ui-datepicker-multi .ui-datepicker-buttonpane { clear:left; }
-.ui-datepicker-row-break { clear:both; width:100%; }
+.ui-datepicker-row-break { clear:both; width:100%; font-size:0em; }
 
 /* RTL support */
 .ui-datepicker-rtl { direction: rtl; }