Remove obsolete code

Remove obsolete code

ChromeHistoryClient is no longer a HistoryServiceObserver, so remove
the cleanup code that dealt with that.

Fix error path when HistoryService::Init() fails in TestingProfile by:
- not calling SetTestingFactoryAndUse() with a null testing factory
- returning false when HistoryService::Init() fails.

BUG=373326
Committed: https://crrev.com/f29a43975907fd816dbdfaeb5c0a595a2e1eef17
Cr-Commit-Position: refs/heads/master@{#314385}

[Jay Civelli, 2015-02-03 18:06:26]

jcivelli@chromium.org changed reviewers:
+ jcivelli@chromium.org

[Jay Civelli, 2015-02-03 18:06:26]

lgtm

[sdefresne, 2015-02-03 18:09:10]

sdefresne@chromium.org changed reviewers:
- jcivelli@google.com

[sdefresne, 2015-02-03 18:09:21]

The CQ bit was checked by sdefresne@chromium.org

[commit-bot: I haz the power, 2015-02-03 18:10:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/894783002/1

[commit-bot: I haz the power, 2015-02-03 18:12:45]

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

[commit-bot: I haz the power, 2015-02-03 18:12:46]

Try jobs failed on following builders:
  ios_dbg_simulator on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/ios_dbg_simulator...)
  ios_rel_device_ng on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/ios_rel_device_ng...)
  ios_rel_device_ninja_ng on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/ios_rel_device_ni...)
  mac_chromium_rel_ng on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[sdefresne, 2015-02-03 18:54:45]

The CQ bit was checked by sdefresne@chromium.org

[commit-bot: I haz the power, 2015-02-03 18:55:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/894783002/20001

[commit-bot: I haz the power, 2015-02-03 19:41:01]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-02-03 19:42:12]

Patchset 2 (id:??) landed as
https://crrev.com/f29a43975907fd816dbdfaeb5c0a595a2e1eef17
Cr-Commit-Position: refs/heads/master@{#314385}