[Feature Request] Mouse Lock API support

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Play some Quake 2 GWT
2. Use mouse to aim
3. Move mouse outside window

What is the expected output? What do you see instead?

Currently if you move the mouse outside the browser window, quake 2 can no 
longer use it for aiming.  It would be nice to be able to lock the mouse so we 
can have that full FPS feel.

What version of the product are you using? On what operating system?

I'm running Chrome on Windows 7 x64 (currently API support is only in Canary 
and nightly builds and can be turned on at about:flags, next Dev build should 
have support as well).  From what I've read it sounds like Firefox is also 
getting support.

Please provide any additional information below.

https://developer.mozilla.org/en/API/Mouse_Lock_API appears to be a reference 
for the API.

Original issue reported on code.google.com by megazzt on 29 Nov 2011 at 3:29