Reset some UMA stability stats on a version change.

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 0bfdd73e456548c1a90854dd6271a66c214dc35e..a4ac7ebb37b56929a32bc5423bbf2310e9048a3e 100644
--- a/components/metrics/metrics_provider.cc
+++ b/components/metrics/metrics_provider.cc
@@ -33,6 +33,9 @@ void MetricsProvider::ProvideStabilityMetrics(
     SystemProfileProto* system_profile_proto) {
 }
 
+void MetricsProvider::ClearSavedStabilityMetrics() {
+}
+
 void MetricsProvider::ProvideGeneralMetrics(
     ChromeUserMetricsExtension* uma_proto) {
 }