Allow max length of "URLs" of map and map element to more than 255

Steps to reproduce:

1. Display Monitoring → Problem page and copy url
   For exsample, copy url follow:

   http://xxx.xxx.xxx.xxx/zabbix/zabbix.php?show=1&name=&inventory%5B0%5D%5Bfield%5D=type&inventory%5B0%5D%5Bvalue%5D=&evaltype=0&tags%5B0%5D%5Btag%5D=&tags%5B0%5D%5Boperator%5D=0&tags%5B0%5D%5Bvalue%5D=&show_tags=3&tag_name_format=0&tag_priority=&show_opdata=0&show_timeline=1&filter_name=&filter_show_counter=0&filter_custom_time=0&sort=clock&sortorder=DESC&age_state=0&show_suppressed=0&unacknowledged=0&compact_view=0&details=0&highlight_row=0&action=problem.view

2. Create new map "MapA" and set the copied url to "URL"
3. Display "MapA" and click link that setting by step2

Result:
The following error message is displayed.
Class not found.

Expected:
The url set in the map settings "URL" is displayed correctly.

This problem also occurs with setting the "URL" for the elements of the map.