[Cleanup] Remove a reference to the FILE thread.

chrome/browser/metrics/antivirus_metrics_provider_win_unittest.cc

Index: chrome/browser/metrics/antivirus_metrics_provider_win_unittest.cc
diff --git a/chrome/browser/metrics/antivirus_metrics_provider_win_unittest.cc b/chrome/browser/metrics/antivirus_metrics_provider_win_unittest.cc
index 3e027e0f75715bb861277bcf49a1ac28916a2825..dbfa3b68d24432988150f06888415f671f0d9049 100644
--- a/chrome/browser/metrics/antivirus_metrics_provider_win_unittest.cc
+++ b/chrome/browser/metrics/antivirus_metrics_provider_win_unittest.cc
@@ -109,8 +109,8 @@ TEST_P(AntiVirusMetricsProviderTest, DISABLED_GetMetricsFullName) {
   ASSERT_TRUE(thread_checker_.CalledOnValidThread());
   base::HistogramTester histograms;
   SetFullNamesFeatureEnabled(expect_unhashed_value_);
-  // Make sure the I/O is happening on the FILE thread by disallowing it on
-  // the main thread.
+  // Make sure the I/O is happening on a valid thread by disallowing it on the
+  // main thread.
   bool previous_value = base::ThreadRestrictions::SetIOAllowed(false);
   provider_->GetAntiVirusMetrics(
       base::Bind(&AntiVirusMetricsProviderTest::GetMetricsCallback,