Some unittest failed with Check failed: prefs_->FindPreference(pref_name_). brave.theme.type not registered.

[simonhong]

This is regression of brave/brave-core#351

[ RUN      ] AutoplayPermissionContextTests.TestInsecureQueryingUrl
[17476:5572:0830/002754.806:1061176015:FATAL:pref_member.cc(39)] Check failed: prefs_->FindPreference(pref_name_). brave.theme.type not registered.
Backtrace:
        base::debug::StackTrace::StackTrace [0x00007FFA44AD11E5+101] (C:\Projects\brave\brave-browser\src\base\debug\stack_trace_win.cc:286)
        base::debug::StackTrace::StackTrace [0x00007FFA44AD021F+31] (C:\Projects\brave\brave-browser\src\base\debug\stack_trace.cc:199)
        logging::LogMessage::~LogMessage [0x00007FFA44B38C36+134] (C:\Projects\brave\brave-browser\src\base\logging.cc:600)
        subtle::PrefMemberBase::Init [0x00007FFA70C96307+567] (C:\Projects\brave\brave-browser\src\components\prefs\pref_member.cc:42)
        subtle::PrefMemberBase::Init [0x00007FFA70C960BF+79] (C:\Projects\brave\brave-browser\src\components\prefs\pref_member.cc:31)
        PrefMember<int>::Init [0x00007FF6AF2F5F92+50] (C:\Projects\brave\brave-browser\src\components\prefs\pref_member.h:175)
        BraveThemeService::Init [0x00007FF6AF2F5F13+195] (C:\Projects\brave\brave-browser\src\brave\browser\themes\brave_theme_service.cc:48)
        ThemeServiceFactory::BuildServiceInstanceFor [0x00007FF6B159C574+84] (C:\Projects\brave\brave-browser\src\chrome\browser\themes\theme_service_factory.cc:67)
        BrowserContextKeyedServiceFactory::BuildServiceInstanceFor [0x00007FFA70B28D3F+47] (C:\Projects\brave\brave-browser\src\components\keyed_service\content\browser_context_keyed_service_fact
ory.cc:97)
        KeyedServiceFactory::GetServiceForContext [0x00007FFA63C5859D+1085] (C:\Projects\brave\brave-browser\src\components\keyed_service\core\keyed_service_factory.cc:89)
        KeyedServiceFactory::CreateServiceNow [0x00007FFA63C59873+35] (C:\Projects\brave\brave-browser\src\components\keyed_service\core\keyed_service_factory.cc:139)
        DependencyManager::CreateContextServices [0x00007FFA63C521B4+708] (C:\Projects\brave\brave-browser\src\components\keyed_service\core\dependency_manager.cc:71)
        BrowserContextDependencyManager::DoCreateBrowserContextServices [0x00007FFA70B2149E+382] (C:\Projects\brave\brave-browser\src\components\keyed_service\content\browser_context_dependency_m
anager.cc:48)
        BrowserContextDependencyManager::CreateBrowserContextServicesForTest [0x00007FFA70B214F3+35] (C:\Projects\brave\brave-browser\src\components\keyed_service\content\browser_context_dependen
cy_manager.cc:38)
        TestingProfile::Init [0x00007FF6AFCDB711+2017] (C:\Projects\brave\brave-browser\src\chrome\test\base\testing_profile.cc:511)
        TestingProfile::TestingProfile [0x00007FF6AFCDC4F7+1287] (C:\Projects\brave\brave-browser\src\chrome\test\base\testing_profile.cc:368)
        TestingProfile::Builder::Build [0x00007FF6AFCE1A84+676] (C:\Projects\brave\brave-browser\src\chrome\test\base\testing_profile.cc:1089)
        ChromeRenderViewHostTestHarness::CreateBrowserContext [0x00007FF6AFCDA125+85] (C:\Projects\brave\brave-browser\src\chrome\test\base\chrome_render_view_host_test_harness.cc:79)
        content::RenderViewHostTestHarness::SetUp [0x00007FF6AFD15EEE+830] (C:\Projects\brave\brave-browser\src\content\public\test\test_renderer_host.cc:295)
        AutoplayPermissionContextTests::SetUp [0x00007FF6AD0129AE+30] (C:\Projects\brave\brave-browser\src\brave\browser\autoplay\autoplay_permission_context_unittest.cc:62)
        testing::internal::HandleExceptionsInMethodIfSupported<testing::Test,void> [0x00007FF6AD10D24F+79] (C:\Projects\brave\brave-browser\src\third_party\googletest\src\googletest\src\gtest.cc:
2492)