Fix php7.x warning on count

[eileenmcnaughton]

Overview

Fixes a warning when php 7.2 tries to count on a null value
Before

After

Gone

Technical Details

This error occurs if you try to do count on a variable that is NULL

Comments

[civibot]

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[colemanw]

Looks like a safe fix.

[mattwire]

Noting that this fix is because the smarty tpl processor is doing a "count"