Created methods to surface zone memory information for each isolate and thread in JSON.

runtime/vm/service.cc

Index: runtime/vm/service.cc
diff --git a/runtime/vm/service.cc b/runtime/vm/service.cc
index dce3eace094526f7a174917c6e957cd7111e8aa4..b579354fdcb55900c7bae4f13b530a8df08db8de 100644
--- a/runtime/vm/service.cc
+++ b/runtime/vm/service.cc
@@ -3759,13 +3759,12 @@ static bool GetVersion(Thread* thread, JSONStream* js) {
 class ServiceIsolateVisitor : public IsolateVisitor {
  public:
   explicit ServiceIsolateVisitor(JSONArray* jsarr) : jsarr_(jsarr) {}
-
   virtual ~ServiceIsolateVisitor() {}
 
   void VisitIsolate(Isolate* isolate) {
     if ((isolate != Dart::vm_isolate()) &&
         !ServiceIsolate::IsServiceIsolateDescendant(isolate)) {
-      jsarr_->AddValue(isolate);
+      jsarr_->AddValue(isolate, false);
     }
   }