Starting a refactor to allow adding metrics on upload.

components/metrics/metrics_provider.cc

Index: components/metrics/metrics_provider.cc
diff --git a/components/metrics/metrics_provider.cc b/components/metrics/metrics_provider.cc
index a4ac7ebb37b56929a32bc5423bbf2310e9048a3e..830deacce5acddd1716cba5cba97e65d8a1c93ad 100644
--- a/components/metrics/metrics_provider.cc
+++ b/components/metrics/metrics_provider.cc
@@ -21,6 +21,9 @@ void MetricsProvider::OnRecordingEnabled() {
 void MetricsProvider::OnRecordingDisabled() {
 }
 
+void MetricsProvider::OnCollectFinalMetrics() {
+}
+
 void MetricsProvider::ProvideSystemProfileMetrics(
     SystemProfileProto* system_profile_proto) {
 }