Factor out a device object for RawInput gamepads

RawInputDataFetcher previously stored information about each connected
gamepad in a RawGamepadInfo object internal to the data fetcher. This
CL renames the object to RawInputGamepadDeviceWin and moves more of the
capabilities and polling logic into that class.

BUG=749295

Change-Id: I9b2ad1f2712e3c14289a9d9a159a04c4cf952d4e
Reviewed-on: https://chromium-review.googlesource.com/875194
Commit-Queue: Matt Reynolds <mattreynolds@chromium.org>
Reviewed-by: Brandon Jones <bajones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#530682}
5 files changed