Fixes #1922: PHP strict convention corrected in template

layouts/v7/modules/Portal/ListViewContents.tpl

@@ -122,7 +122,10 @@
 					{/foreach}
 					{if $PAGING_INFO['recordCount'] eq '0'}
 						<tr class="emptyRecordsDiv">
-							{assign var=COLSPAN_WIDTH value={php7_count($LISTVIEW_HEADERS)}+1}
+							{assign var=COLSPAN_WIDTH value=1}
+							{if isset($LISTVIEW_HEADERS)}
+								{assign var=COLSPAN_WIDTH value=php7_count($LISTVIEW_HEADERS)+1}
+							{/if}
 							<td colspan="{$COLSPAN_WIDTH}">
 								<div class="emptyRecordsContent">
 									{assign var=SINGLE_MODULE value="SINGLE_$MODULE"}