Squashed commit of the following:

commit e2a8165560c7ec6be2d5650e0a3c6a4b520d1f56
Author: Joel Croteau <jcroteau@gmail.com>
Date:   Fri Feb 21 01:40:50 2014 -0800

    Fix indentation in fillMouseEventData

commit a5d620164e2ab7cb7ba61803c1eedb53f888f4cb
Author: Joel Croteau <jcroteau@gmail.com>
Date:   Thu Feb 20 23:56:01 2014 -0800

    Remove dependency on Browser.getMovementX/Y

commit 2e4f0a4c5fc9ab1857e33862c49e20c1418320c2
Author: Joel Croteau <jcroteau@gmail.com>
Date:   Thu Feb 20 10:27:52 2014 -0800

    Fix error that was causing FillMouseEventData to fail with SAFE_HEAP enabled

    The parentheses without semicolons generated when using SAFE_HEAP
    caused the compiled code to generate SAFE_HEAP_STORE is not a function
    errors.

commit 470dbf6bcb3f88c809b3fea41e197680eda08c7e
Author: Joel Croteau <jcroteau@gmail.com>
Date:   Thu Feb 20 07:12:02 2014 -0800

    Fix bug causing incorrect movement values in mouse events

    This adds code to correctly set the movementX and movementY members
    of EmscriptenMouseEvents sent to callback functions by the HTML5
    event library. movementX and movementY are not members of the base
    HTML5 mouse event, so we need to add extra code to retrieve them
    for our events.