Live Reloading - should all styles be cleared before reapplying?

Take for instance `background_color`. Try this:
1. Turn on live reloading
2. style an element and add a background color... say `color.blue`
3. change it to `color.red`. save. app updates to red.
4. now just comment it out and save. color stays red.

I'm wondering if we should go through all the elements and remove any styles (or set the elements back to their "default" state) before reapplying the styles.

Thoughts?

No files or tests are named. Reproduce the live-reloading steps in the issue, then trace the style reapplication path to determine how previously applied styles are handled. Done means commenting out the background color removes the old color instead of leaving it visible.

Written by the indexing model from the issue text.