Fix crash in protocol perf test.

Fix crash in protocol perf test.

CursorShapeStub is being called in perf tests and the test was
returning NULL for the cursor stub which causes it to crash.

Committed: https://crrev.com/93a39f2bcde1d6309f9fcf5ae0d0402cdc32b8af
Cr-Commit-Position: refs/heads/master@{#295858}

[Sergey Ulanov, 2014-09-20 00:06:18]

Patchset #2 (id:20001) has been deleted

[Sergey Ulanov, 2014-09-20 00:06:26]

sergeyu@chromium.org changed reviewers:
+ rmsousa@chromium.org

[rmsousa, 2014-09-20 00:15:28]

lgtm

[Sergey Ulanov, 2014-09-20 00:20:25]

The CQ bit was checked by sergeyu@chromium.org

[commit-bot: I haz the power, 2014-09-20 00:21:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/586943002/40001

[commit-bot: I haz the power, 2014-09-20 02:22:53]

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

[commit-bot: I haz the power, 2014-09-20 02:22:54]

Exceeded time limit waiting for builds to trigger.

[Sergey Ulanov, 2014-09-20 04:33:49]

The CQ bit was checked by sergeyu@chromium.org

[commit-bot: I haz the power, 2014-09-20 04:34:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/586943002/40001

[commit-bot: I haz the power, 2014-09-20 13:13:02]

Committed patchset #2 (id:40001) as 770ae77b7aadf9869abc907bf3c8982375326ebf

[commit-bot: I haz the power, 2014-09-20 13:13:58]

Patchset 2 (id:??) landed as
https://crrev.com/93a39f2bcde1d6309f9fcf5ae0d0402cdc32b8af
Cr-Commit-Position: refs/heads/master@{#295858}