Content: Save and Publish Button remains in a constant spinning state despite an error being thrown

[zcolah]

Problem
Save and Publish Button remains in a constant spinning state despite the save failing due to an error and stops spinning and publishes once the next save is tried. See Loom:
https://www.loom.com/share/e4f77a151f4946508d5bccca063b3799

Solution
If a save is not possible, throw the error, and stop the button from spinning. The button should instead just default back to it's default green save & publish state. Please also test and ensure this happens when the button is just Publish (and not save and publish).