Mitigate black video thumbnails provided by Android

Description

Android may generate black thumbnails without warning in ThumbnailUtils.createVideoThumbnail. This commit mitigate this issue by checking if the returned bitmap is empty

Motivation and Context

How Has This Been Tested?

Screenshots / GIFs (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Enhancement (non-breaking change which cleans up / improves existing functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the CONTRIBUTING section of the README document.

Resolves