I have similar question with "Display a block even if it is empty" about blocks generated with views 3.5.
Views has a somewhat hidden feature for setting the behavior when you have no results.
If you edit the view and click on Advanced, you will see some new settings:
Click on add next to NO RESULTS BEHAVIOR. You will then get a modal with a ton of choices. You should be able to use the textarea or markup options to plop in a This should force the block to not be "empty". You could also set a message, etc.
You can also always show the advanced options if you visit admin/structure/views/settings
I typically always set "Always show the master display" and "Always show advanced display settings". There are some other useful settings on admin/structure/views/settings/advanced