Deleting a single slide shouldn't exit the story creation mode

[megsfulton]

What happens:

1. Take a photo/video or select a photo to add
2. Drag the thumbnail to delete it
3. Kanvas closes and you return the main WP view

What I expected:

1. Take a photo/video or select a photo to add
2. Drag the thumbnail to delete it
3. Return to the camera capture view to take a new photo or select a new photo