Speculatively enable WebNavigationApiTest.UserAction on Windows

This test has been disabled on Windows as flaky. Running locally 100
iterations of the test passed successfully, so this CL enables it.

Bug: 662160
Change-Id: I21d192e02b157c35cb95e9aa6f5ad40425d16ff4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2141135
Commit-Queue: Nasko Oskov <nasko@chromium.org>
Auto-Submit: Nasko Oskov <nasko@chromium.org>
Reviewed-by: Łukasz Anforowicz <lukasza@chromium.org>
Cr-Commit-Position: refs/heads/master@{#757506}

chrome/browser/extensions/api/web_navigation/web_navigation_apitest.cc

@@ -323,13 +323,7 @@ IN_PROC_BROWSER_TEST_F(WebNavigationApiTest, FilteredTest) {
   ASSERT_TRUE(RunExtensionTest("webnavigation/filtered")) << message_;
 }
 
-// Flaky on Windows. See http://crbug.com/662160.
-#if defined(OS_WIN)
-#define MAYBE_UserAction DISABLED_UserAction
-#else
-#define MAYBE_UserAction UserAction
-#endif
-IN_PROC_BROWSER_TEST_F(WebNavigationApiTest, MAYBE_UserAction) {
+IN_PROC_BROWSER_TEST_F(WebNavigationApiTest, UserAction) {
   content::IsolateAllSitesForTesting(base::CommandLine::ForCurrentProcess());
   ASSERT_TRUE(StartEmbeddedTestServer());