Integrated Video Tutorials tab is visible even if empty

When videos are enabled in the Help tab (i.e. 'Add Videos to Contextual Help' is enabled) the video tab appears even if empty. If there are no relevant videos for that page, the Videos tab should be hidden.

For example, if the videos for the dashboard are disabled (Admin Bar, Dashboard, QuickPress, Change Password), the Videos tab will still display for this page, but be empty. This tab should conditionally display only if it is not empty.