Make sure that s_platform is non-null

Make sure that s_platform is non-null

Currently s_platform can be null in platform_unittests.
This CL introduces DummyPlatform and makes sure that s_platform is non-null
(except after Platform::shutdown).

BUG=593269
Committed: https://crrev.com/f80d2873f5d74c33b908be46dd57ba01d5af6c36
Cr-Commit-Position: refs/heads/master@{#380397}

[haraken, 2016-03-10 11:18:34]

haraken@chromium.org changed reviewers:
+ sigbjornf@opera.com

[haraken, 2016-03-10 11:18:35]

PTAL

[sof, 2016-03-10 11:41:10]

lgtm

[haraken, 2016-03-10 11:42:56]

The CQ bit was checked by haraken@chromium.org

[commit-bot: I haz the power, 2016-03-10 11:43:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1785483003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1785483003/1

[commit-bot: I haz the power, 2016-03-10 12:47:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-03-10 12:48:50]

Description was changed from

==========
Make sure that s_platform is non-null

Currently s_platform can be null in platform_unittests.
This CL introduces DummyPlatform and makes sure that s_platform is non-null
(except after Platform::shutdown).

BUG=593269
==========

to

==========
Make sure that s_platform is non-null

Currently s_platform can be null in platform_unittests.
This CL introduces DummyPlatform and makes sure that s_platform is non-null
(except after Platform::shutdown).

BUG=593269

Committed: https://crrev.com/f80d2873f5d74c33b908be46dd57ba01d5af6c36
Cr-Commit-Position: refs/heads/master@{#380397}
==========

[commit-bot: I haz the power, 2016-03-10 12:48:51]

Patchset 1 (id:??) landed as
https://crrev.com/f80d2873f5d74c33b908be46dd57ba01d5af6c36
Cr-Commit-Position: refs/heads/master@{#380397}