Disable flaky NetworkErrorScreenTest.HideCallback

TBR=achuith@chromium.org

Bug: 1010866
Change-Id: Idb04a7a87cfd1bf71e79e90f2202010954f711ba
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1838793Reviewed-by: Yoichi Osato <yoichio@chromium.org>
Commit-Queue: Yoichi Osato <yoichio@chromium.org>
Auto-Submit: Yoichi Osato <yoichio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#702716}

chrome/browser/chromeos/login/error_screen_browsertest.cc

@@ -184,7 +184,7 @@ IN_PROC_BROWSER_TEST_F(NetworkErrorScreenTest, ConnectRequestCallback) {
 }
 
 // Test HideCallback is called after screen hides.
-IN_PROC_BROWSER_TEST_F(NetworkErrorScreenTest, HideCallback) {
+IN_PROC_BROWSER_TEST_F(NetworkErrorScreenTest, DISABLED_HideCallback) {
   bool callback_called = false;
   GetScreen()->SetHideCallback(
       base::BindLambdaForTesting([&]() { callback_called = true; }));