Make --enable-benchmarking not affect metrics recording.

ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.mm

Index: ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.mm
diff --git a/ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.mm b/ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.mm
index 7c7340b50e1facb8468d0224c67b8b992b3d5196..d45a42d0dea3469f3975d9566f3ab9768764af10 100644
--- a/ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.mm
+++ b/ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.mm
@@ -98,11 +98,6 @@ bool IOSChromeMetricsServicesManagerClient::IsMetricsReportingEnabled() {
   return enabled_state_provider_->IsReportingEnabled();
 }
 
-bool IOSChromeMetricsServicesManagerClient::OnlyDoMetricsRecording() {
-  const base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
-  return cmdline->HasSwitch(switches::kIOSMetricsRecordingOnly);
-}
-
 metrics::MetricsStateManager*
 IOSChromeMetricsServicesManagerClient::GetMetricsStateManager() {
   DCHECK(thread_checker_.CalledOnValidThread());