Add native_display_delegate_proxy.cc to the list of files that can use AllowIO.

NativeDisplayDelegateProxy needs to read a file which is necessary to start chrome on UI thread. The file is on tmpfs, so it should be fast.

I've got jam@'s agreement, who is the owner of base/threading/thread_restriction*, in https://codereview.chromium.org/854203002/

BUG=None
R=phajdan.jr@chromium.org

Committed: https://chromium.googlesource.com/chromium/src/+/756e484f8bc79091a8846a19b39ccc28f79e8d8d

[oshima, 2015-01-22 20:44:36]

oshima@chromium.org changed reviewers:
+ phajdan.jr@chromium.org

[Paweł Hajdan Jr., 2015-01-23 10:47:57]

LGTM

[oshima, 2015-01-23 16:51:33]

The CQ bit was checked by oshima@chromium.org

[commit-bot: I haz the power, 2015-01-23 16:52:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/866103002/1

[commit-bot: I haz the power, 2015-01-23 16:59:45]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-01-23 16:59:46]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[commit-bot: I haz the power, 2015-01-23 21:32:30]

Patchset 1 (id:??) landed as
https://crrev.com/756e484f8bc79091a8846a19b39ccc28f79e8d8d
Cr-Commit-Position: refs/heads/master@{#312932}

[oshima, 2015-01-23 21:32:35]

Committed patchset #1 (id:1) manually as
756e484f8bc79091a8846a19b39ccc28f79e8d8d (presubmit successful).