Move tests from test_shell_tests to content_unittests.

Move tests from test_shell_tests to content_unittests.

These tests don't depend on webkit/tools/test_shell/test_shell_test.h
and can be moved to content_unittests.

Some tests were relying on the MessageLoop created by TestShell. I've
updated them to create their own MessageLoop.

BUG=126514
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=177180

[jam, 2013-01-15 01:35:32]

lgtm

[commit-bot: I haz the power, 2013-01-15 18:02:57]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tony@chromium.org/11883022/1

[commit-bot: I haz the power, 2013-01-15 19:06:00]

Retried try job too often on android_clang_dbg for step(s) build

[commit-bot: I haz the power, 2013-01-15 21:53:01]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tony@chromium.org/11883022/23001

[commit-bot: I haz the power, 2013-01-16 01:10:22]

Failed to trigger a try job on android_dbg
HTTP Error 400: Bad Request

[commit-bot: I haz the power, 2013-01-16 01:11:00]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tony@chromium.org/11883022/37002

[commit-bot: I haz the power, 2013-01-16 03:28:51]

Retried try job too often on win for step(s) compile

[commit-bot: I haz the power, 2013-01-16 17:49:47]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/tony@chromium.org/11883022/37002

[commit-bot: I haz the power, 2013-01-16 18:45:35]

Change committed as 177180