Fix flake in TrialComparisonCertVerifierFeatureEnabledTest.

The test was checking the CertVerifier_Job_Latency_TrialSecondary and
CertVerifier_TrialComparisonResult histogram values, but those histograms are
recorded by a background task that is independent of page loading, so they
may not be finished by the time the ui_test_utils::NavigateToURL call
completes.

Checking the CertVerifier_Job_Latency_TrialPrimary histogram is sufficient to
tell whether the trial was enabled or not, and that histogram is recorded
synchronously when the main verification completes, so should always be present
when NavigateToURL returns.

Bug: 981325
Change-Id: I1c7ab99d79e5ba58d4bc561d88b00024e22f3cd8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1689399Reviewed-by: Eric Roman <eroman@chromium.org>
Commit-Queue: Matt Mueller <mattm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#675820}

chrome/browser/net/trial_comparison_cert_verifier_browsertest.cc

@@ -35,8 +35,6 @@ IN_PROC_BROWSER_TEST_F(TrialComparisonCertVerifierTest, TrialDisabled) {
   SubprocessMetricsProvider::MergeHistogramDeltasForTesting();
   histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency", 1);
   histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialPrimary", 0);
-  histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialSecondary", 0);
-  histograms.ExpectTotalCount("Net.CertVerifier_TrialComparisonResult", 0);
 }
 
 class TrialComparisonCertVerifierFeatureEnabledTest
@@ -69,18 +67,10 @@ IN_PROC_BROWSER_TEST_F(TrialComparisonCertVerifierFeatureEnabledTest,
   SubprocessMetricsProvider::MergeHistogramDeltasForTesting();
   histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency", 1);
   histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialPrimary", 0);
-  histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialSecondary", 0);
-  histograms.ExpectTotalCount("Net.CertVerifier_TrialComparisonResult", 0);
 }
 
-// Flaky on Mac. See https://crbug.com/981325.
-#if defined(OS_MACOSX)
-#define MAYBE_TrialEnabledPrefEnabled DISABLED_TrialEnabledPrefEnabled
-#else
-#define MAYBE_TrialEnabledPrefEnabled TrialEnabledPrefEnabled
-#endif
 IN_PROC_BROWSER_TEST_F(TrialComparisonCertVerifierFeatureEnabledTest,
-                       MAYBE_TrialEnabledPrefEnabled) {
+                       TrialEnabledPrefEnabled) {
   safe_browsing::SetExtendedReportingPref(browser()->profile()->GetPrefs(),
                                           true);
 
@@ -96,16 +86,10 @@ IN_PROC_BROWSER_TEST_F(TrialComparisonCertVerifierFeatureEnabledTest,
     // If both the dual cert verifier trial feature and the builtin verifier
     // feature are enabled, the dual cert verifier trial should not be used.
     histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialPrimary", 0);
-    histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialSecondary",
-                                0);
-    histograms.ExpectTotalCount("Net.CertVerifier_TrialComparisonResult", 0);
     return;
   }
 #endif
   histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialPrimary", 1);
-  histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialSecondary", 1);
-  histograms.ExpectUniqueSample("Net.CertVerifier_TrialComparisonResult",
-                                net::TrialComparisonCertVerifier::kEqual, 1);
 }
 
 #if BUILDFLAG(BUILTIN_CERT_VERIFIER_FEATURE_SUPPORTED)
@@ -148,7 +132,5 @@ IN_PROC_BROWSER_TEST_F(
   // If both the dual cert verifier trial feature and the builtin verifier
   // feature are enabled, the dual cert verifier trial should not be used.
   histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialPrimary", 0);
-  histograms.ExpectTotalCount("Net.CertVerifier_Job_Latency_TrialSecondary", 0);
-  histograms.ExpectTotalCount("Net.CertVerifier_TrialComparisonResult", 0);
 }
 #endif