Bug 197988

The following API test is crashing on Mojave Release and Debug builds TestWebKitAPI.Challenge.ClientCertificate Verified locally with run-api-tests TestWebKitAPI.Challenge.ClientCertificate --debug Crash: _RegisterApplication(), FAILED TO establish the default connection to the WindowServer, _CGSDefaultConnection() is NULL. 1 0x10635dc79 WTFCrash 2 0x104bd01b9 WTF::CrashOnOverflow::crash() 3 0x104bd01a9 WTF::CrashOnOverflow::overflowed() 4 0x104c2d06b WTF::Vector<WTF::RetainPtr<NSString>, 0ul, WTF::CrashOnOverflow, 16ul>::at(unsigned long) const 5 0x104c2806d WTF::Vector<WTF::RetainPtr<NSString>, 0ul, WTF::CrashOnOverflow, 16ul>::operator[](unsigned long) const 6 0x104c27d00 Challenge_ClientCertificate_Test::TestBody() 7 0x105234d0e void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) 8 0x10520468b void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) 9 0x1052045b6 testing::Test::Run() 10 0x1052057c5 testing::TestInfo::Run() 11 0x1052066af testing::TestCase::Run() 12 0x105212314 testing::internal::UnitTestImpl::RunAllTests() 13 0x105238e8e bool testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) 14 0x105211deb bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) 15 0x105211cc0 testing::UnitTest::Run() 16 0x10506e931 RUN_ALL_TESTS() 17 0x10506e8c1 TestWebKitAPI::TestsController::run(int, char**) 18 0x1051d1a1e main 19 0x7fff6f2b33d5 start 20 0x2