Revert of Disable flaky CommandLineExtensionsDontLoad test

chrome/browser/extensions/extension_startup_browsertest.cc

Index: chrome/browser/extensions/extension_startup_browsertest.cc
diff --git a/chrome/browser/extensions/extension_startup_browsertest.cc b/chrome/browser/extensions/extension_startup_browsertest.cc
index 8ecfb4ab10bff04b0f5cd581ae6fd404bb70fb77..a50f7568317c65d1e086411ae7516f0129a351e4 100644
--- a/chrome/browser/extensions/extension_startup_browsertest.cc
+++ b/chrome/browser/extensions/extension_startup_browsertest.cc
@@ -284,9 +284,8 @@
   }
 };
 
-// Flaky test crbug.com/716727
 IN_PROC_BROWSER_TEST_F(ExtensionsLoadTestWithLoginScreenApps,
-                       DISABLED_CommandLineExtensionsDontLoad) {
+                       CommandLineExtensionsDontLoad) {
   // The --load-extension command line flag should not be applied to the sign-in
   // profile.
   EXPECT_EQ(0, GetNonComponentEnabledExtensionCount(