Error in host dashboard view if multi page dashboard's first page is empty

Steps to reproduce:

1. Navigate to Templates and select Dashboards for Linux by Zabbix agent template.
2. Create a new dashboard with name 'Test'.
3. Leave the first dashboard page empty and add the second page.
4. Add one widget of your choice to the second dashboard page (optional).
5. Save 'Test' dashboard.
6. Navigate to Zabbix server host dashboards and select 'Test' dashboard.

Result:

Broken host dashboard view, dashboard page tabs not displayed, slideshow not working and no content of any dashboard page.

Expected:
Dashboard page tabs displayed, slide show is working, the first page is empty and the second with previously added widget.

Note:
For 7.0.0alpha4 (master) this issue will be fixed in ZBXNEXT-8421 (Improve host dashboard navigation).