Error with warining and array_map()

I had the same issue this morning after upgradind to WP version 4.4.
The issues seems related to bad use of $terms variable in function get_the_terms at line 1158 in WP core code. I had to verify if $terms was an array, if not make a new instance of it:

$terms = is_array($terms) ? $terms : array();

I am confident in a minor release including this bugfix. Meanwhile my solution seems to work fine.

I had the same problem. WP released a patch for 4.4:

https://wordpress.org/support/topic/getting-warning-array_map-argument-2-should-be-in-array

Hope that helps!

Just to let you know a new version of Events Manager has just been released that should fix this issue.