Remove shared_handles.{cc,h}

Remove shared_handles.{cc,h}

As far as I can tell, these have unused for at least the last 3 years.

Committed: https://crrev.com/fda4a850b8c1452563f78033d537a7f53220981c
Cr-Commit-Position: refs/heads/master@{#357149}

[rickyz (no longer on Chrome), 2015-10-29 22:28:44]

rickyz@chromium.org changed reviewers:
+ wfh@chromium.org

[Will Harris, 2015-10-30 17:23:36]

lgtm

[rickyz (no longer on Chrome), 2015-10-30 18:06:44]

The CQ bit was checked by rickyz@chromium.org

[commit-bot: I haz the power, 2015-10-30 18:09:01]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1430763002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1430763002/1

[commit-bot: I haz the power, 2015-10-30 18:43:17]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-30 18:44:55]

Patchset 1 (id:??) landed as
https://crrev.com/fda4a850b8c1452563f78033d537a7f53220981c
Cr-Commit-Position: refs/heads/master@{#357149}