Store HID report sizes as uint16_t.

Store HID report sizes as uint16_t.

HID report sizes are unsigned values. In addition they should (because
of the limited size of USB control transfers) never be larger than 64k.
In reality that would be an absolutely enormous report and unlikely to
ever been seen in the wild. By limiting the storage size for report
lengths to a uint16_t we therefore also limit our exposure to being
convinced to allocate unreasonably large buffers by a malicious device.
The Windows HID parser already limits report sizes to a USHORT value.

BUG=

Committed: https://crrev.com/70cdd67c0293cef1216422386ff92018770c4b70
Cr-Commit-Position: refs/heads/master@{#291624}

[rpaquay, 2014-08-24 00:29:19]

lgtm

[Reilly Grant (use Gerrit), 2014-08-24 06:15:40]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2014-08-24 06:16:19]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/reillyg@chromium.org/492963007/1

[commit-bot: I haz the power, 2014-08-24 07:11:59]

Committed patchset #1 (1) as 1ffd11a5d463e32100791a453d47eb8591c08eeb

[commit-bot: I haz the power, 2014-09-10 02:32:32]

Patchset 1 (id:??) landed as
https://crrev.com/70cdd67c0293cef1216422386ff92018770c4b70
Cr-Commit-Position: refs/heads/master@{#291624}