Fix for memory leaks in SpeechRecognitionAudioSinkTest

Several memory leaks in unit test: SpeechRecognitionAudioSinkTest.
Due to uninitialized memory.
This CL is fixing the issue.

BUG=408940, 422164, 422472
TEST=Memory bot for content_unittests

Committed: https://crrev.com/0aef15554835f531e82fc28fb5823a64b4e3e088
Cr-Commit-Position: refs/heads/master@{#299277}

[burnik, 2014-10-11 21:40:08]

Remove suppressions

[burnik, 2014-10-11 22:00:34]

Init bus and data to zero

[burnik, 2014-10-12 18:47:24]

Rebase and clean up

[burnik, 2014-10-12 21:07:39]

burnik@chromium.org changed reviewers:
+ xians@chromium.org

[burnik, 2014-10-12 21:08:36]

A few more memory leaks according to:
https://code.google.com/p/chromium/issues/detail?id=422472

Should now be fixed by this CL.

[no longer working on chromium, 2014-10-13 09:10:19]

On 2014/10/12 21:08:36, burnik wrote:
> A few more memory leaks according to:
> https://code.google.com/p/chromium/issues/detail?id=422472
> 
> Should now be fixed by this CL.

lgtm

[burnik, 2014-10-13 09:51:53]

The CQ bit was checked by burnik@chromium.org

[commit-bot: I haz the power, 2014-10-13 09:52:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/645363005/130001

[commit-bot: I haz the power, 2014-10-13 10:03:05]

Committed patchset #4 (id:130001)

[commit-bot: I haz the power, 2014-10-13 10:03:40]

Patchset 4 (id:??) landed as
https://crrev.com/0aef15554835f531e82fc28fb5823a64b4e3e088
Cr-Commit-Position: refs/heads/master@{#299277}