Make logging of user actions consistent with histograms for OTR.

ios/chrome/browser/metrics/ios_chrome_metrics_service_client.cc

Index: ios/chrome/browser/metrics/ios_chrome_metrics_service_client.cc
diff --git a/ios/chrome/browser/metrics/ios_chrome_metrics_service_client.cc b/ios/chrome/browser/metrics/ios_chrome_metrics_service_client.cc
index 0f94982620d2b97664d6ac985df9d182cf679055..c8a3a751122ce2eb86a75fa9701b1c3d2a98aceb 100644
--- a/ios/chrome/browser/metrics/ios_chrome_metrics_service_client.cc
+++ b/ios/chrome/browser/metrics/ios_chrome_metrics_service_client.cc
@@ -101,10 +101,6 @@ void IOSChromeMetricsServiceClient::SetMetricsClientId(
   crash_keys::SetMetricsClientIdFromGUID(client_id);
 }
 
-bool IOSChromeMetricsServiceClient::IsOffTheRecordSessionActive() {
-  return ::IsOffTheRecordSessionActive();
-}
-
 int32_t IOSChromeMetricsServiceClient::GetProduct() {
   return metrics::ChromeUserMetricsExtension::CHROME;
 }