The chromium team is currently experimenting with a simplified fullscreen UI. Instead of having an annoying prompt to allow sites to go fullscreen, this new user experience will grant them automatically fullscreen access. A bubble will appear appropriately so that you're still able to exit full screen by clicking on it or pressing <Escape> key.
Give it a try now in Dev Channel or Canary by enabling the experimental flag named "Simplified fullscreen / mouse lock UI" at chrome://flags/#simplified-fullscreen-ui and let the chromium team know what you think of it.
For info, the design document is publicly available at