add extra button in Firefox android version to reset playback speed.

[NHM2005]

As there are limited button works on android. Keyboard aren't attached so many features is unavailable in Firefox android version.

So, add and extra button to reset playback speed in one tap.
Also you can extra button to quickly switch to 2x playback speed.
As it is Mobile devices , so I can't reset playback speed quickly.
By tapping R from keyboard.

https://addons.mozilla.org/en-US/android/addon/video-speed-controller-android/