Player movement sometimes randomly becomes "sticky", and fixing this results in losing mouse focus.

What I expected to happen was...:
I expect that my player will move forward only when I press w, and stop when I stop pressing the key. I expect that when I return from the pause/options menu, mouse and crosshair focus will be synchronized.

What actually happened was...:
The player sometimes continues to move forward despite the forward key (w) no longer being pressed. It is possible to stop temporarily by pressing the reverse key (s) but as soon as that key is released, forward movement continues. This issue is temporarily resolved by exiting to the pause/options menu (esc) but upon resuming gameplay, mouse movement and focus is no longer synchronized with the cross-hair. This is only fixed by exiting the game entirely.

Steps to Reproduce:
1. Walk around on land in survival mode in 1.5.2.
2. When movement jams, press escape key.
3. Resume gameplay to find normal walking, but no mouse focus.