Revert of Run app_shell_browsertests and app_shell_unittests on mac trybots and waterfall bots.

Revert of Run app_shell_browsertests and app_shell_unittests on mac trybots and waterfall bots. (patchset #2 id:20001 of https://codereview.chromium.org/822763005/)

Reason for revert:
Mac10.9 Tests (dbg) has been burning since this landed, with consistent failures of a few dozen of the app_shell_browsertests:

failures:
AppViewTest.TestAppViewGoodDataShouldSucceed
HidApiTest.HidApp
HidApiTest.OnDeviceAdded
SystemMemoryApiTest.Memory
SystemCpuApiTest.Cpu
UsbApiTest.ListInterfaces
SystemDisplayApiTest.GetDisplay
SystemStorageEjectApiTest.EjectBadDeviceTest
UsbApiTest.TransferFailure
UsbApiTest.ResetDevice
SystemStorageApiTest.StorageAttachment
SystemStorageEjectApiTest.EjectTest
UsbApiTest.ZeroLengthTransfer
UsbApiTest.InvalidLengthTransfer
UsbApiTest.TransferEvent
UsbApiTest.DeviceHandling
DnsApiTest.DnsExtension
HidApiTest.OnDeviceRemoved
SystemNetworkApiTest.SystemNetworkExtension
SystemStorageApiTest.Storage

Original issue's description:
> Run app_shell_browsertests and app_shell_unittests on mac trybots and waterfall bots.
>
> BUG=399363
>
> Committed: https://crrev.com/527e36e0910f9336cb02ac4ce5d96f4fcf3c4d6d
> Cr-Commit-Position: refs/heads/master@{#309817}

TBR=phajdan.jr@chromium.org,dpranke@chromium.org,yoz@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=399363
Committed: https://crrev.com/617593187a454d2f9d750dbee9520fed3a496a2d
Cr-Commit-Position: refs/heads/master@{#309843}

[Avi (use Gerrit), 2015-01-02 17:48:42]

Created Revert of Run app_shell_browsertests and app_shell_unittests on mac
trybots and waterfall bots.

[commit-bot: I haz the power, 2015-01-02 17:49:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/829093002/1

[commit-bot: I haz the power, 2015-01-02 17:49:54]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-02 17:51:03]

Patchset 1 (id:??) landed as
https://crrev.com/617593187a454d2f9d750dbee9520fed3a496a2d
Cr-Commit-Position: refs/heads/master@{#309843}