Set a "metrics_client_id" crash key instead of "guid" on Mac OS X

components/metrics/test_metrics_service_client.cc

Index: components/metrics/test_metrics_service_client.cc
diff --git a/components/metrics/test_metrics_service_client.cc b/components/metrics/test_metrics_service_client.cc
index 9dcb370eb44f8a904dc126e698aa133786c5d828..b0166729c407bbb31bcf03193757fcbee736113d 100644
--- a/components/metrics/test_metrics_service_client.cc
+++ b/components/metrics/test_metrics_service_client.cc
@@ -26,6 +26,9 @@ void TestMetricsServiceClient::SetMetricsClientId(
   client_id_ = client_id;
 }
 
+void TestMetricsServiceClient::OnRecordingDisabled() {
+}
+
 bool TestMetricsServiceClient::IsOffTheRecordSessionActive() {
   return false;
 }