Revert "OOBE: Restore disabled OobeConfigurationTest tests"

This reverts commit 92c9e3b1.

Reason for revert: Breaks linux-chromeos-rel and linux-chromeos-chrome, see crbug.com/1114140

Original change's description:
> OOBE: Restore disabled OobeConfigurationTest tests
> 
> Seems that changes made in recent month made testing code more
> stable, so tests are not flaky anymore.
> 
> TEST=run tests with --gtest_repeat=25 --gtest_break_on_failure with
>      affinity to 2 codes + simulated CPU load on same cores
> 
> Bug: 997685
> Change-Id: I687e0191bddfe569d5a9fcdf60761c66024e7476
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2339989
> Commit-Queue: Denis Kuznetsov [CET] <antrim@chromium.org>
> Commit-Queue: Roman Sorokin [CET] <rsorokin@chromium.org>
> Reviewed-by: Roman Sorokin [CET] <rsorokin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#795872}

TBR=antrim@chromium.org,rsorokin@chromium.org

Change-Id: I1d820d0b038f2b5bbf536b916475ff3261f11f24
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 997685, 1114140
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2343224Reviewed-by: Dominique Fauteux-Chapleau <domfc@chromium.org>
Commit-Queue: Dominique Fauteux-Chapleau <domfc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795894}

chrome/browser/chromeos/login/configuration_based_oobe_browsertest.cc

@@ -44,6 +44,10 @@
 using testing::_;
 using testing::Invoke;
 
+// Disabled due to flakiness: https://crbug.com/997685.
+#define MAYBE_TestDemoModeOfflineNetwork DISABLED_TestDemoModeOfflineNetwork
+#define MAYBE_TestDemoModeAcceptEula DISABLED_TestDemoModeAcceptEula
+
 namespace chromeos {
 
 // This test case will use
@@ -227,7 +231,8 @@ IN_PROC_BROWSER_TEST_F(OobeConfigurationTest, TestDemoModePreferences) {
 
 // Check that configuration lets correctly use offline demo mode on network
 // screen.
-IN_PROC_BROWSER_TEST_F(OobeConfigurationTest, TestDemoModeOfflineNetwork) {
+IN_PROC_BROWSER_TEST_F(OobeConfigurationTest,
+                       MAYBE_TestDemoModeOfflineNetwork) {
   LoadConfiguration();
   OobeScreenWaiter(DemoPreferencesScreenView::kScreenId).Wait();
   SimulateOfflineEnvironment();
@@ -236,7 +241,7 @@ IN_PROC_BROWSER_TEST_F(OobeConfigurationTest, TestDemoModeOfflineNetwork) {
 
 // Check that configuration lets correctly use offline demo mode on EULA
 // screen.
-IN_PROC_BROWSER_TEST_F(OobeConfigurationTest, TestDemoModeAcceptEula) {
+IN_PROC_BROWSER_TEST_F(OobeConfigurationTest, MAYBE_TestDemoModeAcceptEula) {
   LoadConfiguration();
   OobeScreenWaiter(DemoPreferencesScreenView::kScreenId).Wait();
   SimulateOfflineEnvironment();