Switching reviews causes new comments to be invisible until page reload

[NikhilVerma]

• Open a branch diff with existing reviews
• Add comment
• Clicks another review link on the bottom dialog
• Add another comment (click Comment in comment dialog)

Actual Result

Nothing happens. (But after reloading a page I see new unfinished reviews)

Expected Result

We should either prevent user from switching reviews after starting a new one. Or show the comments for the new review on switch.