-e: When using WebGL Preview builds, Input.GetButton (GetButtonDown, etc) fails to return true when pressing the joystick buttons. The Horizontal and Vertical axis work, but buttons do not.

-repro:
--1. Press play and test the controller for intended functionality: Horizontal axis orbits the camera, 'A' button should scale the cube, 'B' button wobbles, 'X' button flashes it red, 'Y' button jumps.
--2. build for platform to HTML5 WebGL (preview) in Build setting.
--3. Open index.html in browser (verified in Firefox and Chrome),
--4. Test the controller for intended functionality: Horizontal axis orbits the camera, 'A' button should scale the cube, 'B' button wobbles, 'X' button flashes it red, 'Y' button jumps. Verify that its working when pressing any other controls mapped to Fire1, Fire2, Fire3 and Jump.