Media Router: Remove unnecessary and incorrect static_cast in test.

Media Router: Remove unnecessary and incorrect static_cast in test.

The SigninManager object here is in fact of type SigninManager, not
FakeSigninManagerForTesting. The bad cast here caused test failures
in CFI mode [1]. Because the test is not using any members of
FakeSigninManagerForTesting, we can simply remove the cast.

[1] https://build.chromium.org/p/chromium.fyi/builders/CFI%20Linux/builds/5924/steps/unit_tests/logs/MediaRouterContextualMenuUnitTest.Basic

BUG=464797
R=pkasting@chromium.org

Committed: https://crrev.com/b25eb565ec1125425d4777e1a7580b0857c64c53
Cr-Commit-Position: refs/heads/master@{#403483}

[Peter Kasting, 2016-07-01 07:45:36]

LGTM

[pcc1, 2016-07-01 16:35:02]

The CQ bit was checked by pcc@chromium.org

[commit-bot: I haz the power, 2016-07-01 16:35:19]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-01 16:50:16]

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

[commit-bot: I haz the power, 2016-07-01 16:50:16]

Try jobs failed on following builders:
  linux_chromium_chromeos_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[pcc1, 2016-07-01 17:09:46]

The CQ bit was checked by pcc@chromium.org

[pcc1, 2016-07-01 17:09:46]

The patchset sent to the CQ was uploaded after l-g-t-m from
pkasting@chromium.org
Link to the patchset: https://codereview.chromium.org/2118503004/#ps20001
(title: "Add missing #include")

[commit-bot: I haz the power, 2016-07-01 17:10:00]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-01 17:24:35]

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

[commit-bot: I haz the power, 2016-07-01 17:24:36]

Try jobs failed on following builders:
  linux_chromium_chromeos_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[pcc1, 2016-07-01 17:30:25]

The CQ bit was checked by pcc@chromium.org

[pcc1, 2016-07-01 17:30:25]

The patchset sent to the CQ was uploaded after l-g-t-m from
pkasting@chromium.org
Link to the patchset: https://codereview.chromium.org/2118503004/#ps40001
(title: "SigninManagerBase")

[commit-bot: I haz the power, 2016-07-01 17:30:48]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-01 18:24:59]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-07-01 18:25:06]

CQ bit was unchecked.

[commit-bot: I haz the power, 2016-07-01 18:27:09]

Description was changed from

==========
Media Router: Remove unnecessary and incorrect static_cast in test.

The SigninManager object here is in fact of type SigninManager, not
FakeSigninManagerForTesting. The bad cast here caused test failures
in CFI mode [1]. Because the test is not using any members of
FakeSigninManagerForTesting, we can simply remove the cast.

[1]
https://build.chromium.org/p/chromium.fyi/builders/CFI%20Linux/builds/5924/st...

BUG=464797
R=pkasting@chromium.org
==========

to

==========
Media Router: Remove unnecessary and incorrect static_cast in test.

The SigninManager object here is in fact of type SigninManager, not
FakeSigninManagerForTesting. The bad cast here caused test failures
in CFI mode [1]. Because the test is not using any members of
FakeSigninManagerForTesting, we can simply remove the cast.

[1]
https://build.chromium.org/p/chromium.fyi/builders/CFI%20Linux/builds/5924/st...

BUG=464797
R=pkasting@chromium.org

Committed: https://crrev.com/b25eb565ec1125425d4777e1a7580b0857c64c53
Cr-Commit-Position: refs/heads/master@{#403483}
==========

[commit-bot: I haz the power, 2016-07-01 18:27:10]

Patchset 3 (id:??) landed as
https://crrev.com/b25eb565ec1125425d4777e1a7580b0857c64c53
Cr-Commit-Position: refs/heads/master@{#403483}