Fix invalid parameter giving E_WARNING

[demeritcowboy]

Overview

The third param for a quickform hidden element needs to be null not an empty array if not passing in anything.

Before

1. Search for contacts.
2. Choose print/merge document
3. Warning: htmlspecialchars() expects parameter 1 to be string, array given in HTML_Common->_getAttrString() (line 144 of ...civicrm/packages/HTML/Common.php).

After

Technical Details

Comments

This was just added yesterday

[civibot]

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