It seems as if the Android APK, does not include "android.hardware.type.pc" in it's manifest, which would allow android devices to use the keyboard and mouse, as their actual hardware, and not a touch-emulated version.

This would then allow users on chromebooks specifically, to play the game as if it was on PC.

This would also allow those, who attach a keyboard and mouse device to phone and tablets to use the PC type control scheme.

This also does NOT break the ability to switch to touchscreen controls, as this is for the emulated touch-hardware only. So the touchscreen would still properly switch to touch-based controls as needed. 

More implementation information here: https://developer.android.com/topic/arc/input-compatibility

Please let me know if help is needed with implementation, as this is a simple way to gain a mass amount of Minecraft players, by allowing them to use their only "computer" like device, a chromebook. (as chromebooks now run Android Apps and Games within the OS)

I have both a Pixelbook Chromebook, and a Pixel 2 XL device to follow through the testing on.