Changes Windows removable drive listing to include all USB drives.

Some drives do not report themselves as removable despite appearing to a user
to be a removable drive. Particularly this is the case for some USB sticks. We
are fixing this by changing the device listing to list all drives that are 
either removable or attached via USB. We have already done a similar change for 
Chrome OS due to some SD card readers listing themselves as non-removable.
Chrome OS lists all SD or USB drives. However, we do not have a reliable way to
detect SD cards on Windows and Mac so we will continue to use the removable
flag.

BUG=392943
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=282528

[Drew Haven, 2014-07-10 21:08:28]

Here's a companion CL to the Linux one I sent you earlier this week.  This one
is really really short.

[tbarzic, 2014-07-10 21:14:54]

lgtm

[Drew Haven, 2014-07-10 22:13:48]

The CQ bit was checked by haven@chromium.org

[commit-bot: I haz the power, 2014-07-10 22:15:50]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/haven@chromium.org/382023002/30001

[commit-bot: I haz the power, 2014-07-11 02:57:28]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  win8_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/win8_chromium_rel/bui...)

[commit-bot: I haz the power, 2014-07-11 03:35:47]

Change committed as 282528