Use SequencedSocketData in SpdySessionTest.

Use SequencedSocketData in SpdySessionTest.

* Use SequencedSocketData instead of DeterministicSocketData in SpdySessionTest.
* Use nullptr instead of NULL, EXPECT_FALSE() instead of EXPECT_EQ(nullptr), etc.
* Uniformly use RunLoop() instead of MessageLoop::current().
* Remove unnecessary set_connect_data calls.

BUG=492698
Committed: https://crrev.com/273d29cdbe3be5f49e104e67192926dbcac358c1
Cr-Commit-Position: refs/heads/master@{#333122}

[Bence, 2015-06-05 18:10:10]

bnc@chromium.org changed reviewers:
+ rch@chromium.org

[Bence, 2015-06-05 18:10:11]

Ryan: PTAL.  Thanks.

[Ryan Hamilton, 2015-06-05 20:29:03]

YES!!!! lgtm

[Bence, 2015-06-05 20:36:14]

The CQ bit was checked by bnc@chromium.org

[commit-bot: I haz the power, 2015-06-05 20:40:28]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1153653003/40001

[commit-bot: I haz the power, 2015-06-05 20:46:47]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-06-05 20:47:50]

Patchset 3 (id:??) landed as
https://crrev.com/273d29cdbe3be5f49e104e67192926dbcac358c1
Cr-Commit-Position: refs/heads/master@{#333122}