Revert "Add current rss and embedder name to Observatory"

runtime/vm/metrics.cc

Index: runtime/vm/metrics.cc
diff --git a/runtime/vm/metrics.cc b/runtime/vm/metrics.cc
index 94fd0bf63f437cb5b9fe94e993dc2133482d49d3..afb7b879bc9776860101d6464037e4327f9de6a3 100644
--- a/runtime/vm/metrics.cc
+++ b/runtime/vm/metrics.cc
@@ -289,12 +289,8 @@ int64_t MetricIsolateCount::Value() const {
   return Isolate::IsolateListLength();
 }
 
-int64_t MetricCurrentRSS::Value() const {
-  return Service::CurrentRSS();
-}
-
 int64_t MetricPeakRSS::Value() const {
-  return Service::MaxRSS();
+  return OS::MaxRSS();
 }
 
 #define VM_METRIC_VARIABLE(type, variable, name, unit)                         \