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

runtime/vm/json_stream.h

Index: runtime/vm/json_stream.h
diff --git a/runtime/vm/json_stream.h b/runtime/vm/json_stream.h
index bdf1b3a58c70c480a15fde0498afa578ad4b89b9..e49b8468609aeff996b4413223b812e71a78b50d 100644
--- a/runtime/vm/json_stream.h
+++ b/runtime/vm/json_stream.h
@@ -30,6 +30,8 @@ class ServiceEvent;
 class String;
 class TimelineEvent;
 class TimelineEventBlock;
+class Thread;
+class ThreadRegistry;
 class Zone;
 
 
@@ -181,6 +183,9 @@ class JSONStream : ValueObject {
   void PrintValue(Metric* metric);
   void PrintValue(MessageQueue* queue);
   void PrintValue(Isolate* isolate, bool ref = true);
+  void PrintValue(ThreadRegistry* reg);
+  void PrintValue(Thread* thread);
+  void PrintValue(Zone* zone);
   bool PrintValueStr(const String& s, intptr_t offset, intptr_t count);
   void PrintValue(const TimelineEvent* timeline_event);
   void PrintValue(const TimelineEventBlock* timeline_event_block);
@@ -212,6 +217,9 @@ class JSONStream : ValueObject {
   void PrintProperty(const char* name, Metric* metric);
   void PrintProperty(const char* name, MessageQueue* queue);
   void PrintProperty(const char* name, Isolate* isolate);
+  void PrintProperty(const char* name, ThreadRegistry* reg);
+  void PrintProperty(const char* name, Thread* thread);
+  void PrintProperty(const char* name, Zone* zone);
   void PrintProperty(const char* name, const TimelineEvent* timeline_event);
   void PrintProperty(const char* name,
                      const TimelineEventBlock* timeline_event_block);
@@ -331,6 +339,15 @@ class JSONObject : public ValueObject {
   void AddProperty(const char* name, Isolate* isolate) const {
     stream_->PrintProperty(name, isolate);
   }
+  void AddProperty(const char* name, ThreadRegistry* reg) const {
+    stream_->PrintProperty(name, reg);
+  }
+  void AddProperty(const char* name, Thread* thread) const {
+    stream_->PrintProperty(name, thread);
+  }
+  void AddProperty(const char* name, Zone* zone) const {
+    stream_->PrintProperty(name, zone);
+  }
   void AddProperty(const char* name,
                    const TimelineEvent* timeline_event) const {
     stream_->PrintProperty(name, timeline_event);
@@ -386,6 +403,9 @@ class JSONArray : public ValueObject {
   void AddValue(Isolate* isolate, bool ref = true) const {
     stream_->PrintValue(isolate, ref);
   }
+  void AddValue(ThreadRegistry* reg) const { stream_->PrintValue(reg); }
+  void AddValue(Thread* thread) const { stream_->PrintValue(thread); }
+  void AddValue(Zone* zone) const { stream_->PrintValue(zone); }
   void AddValue(Breakpoint* bpt) const { stream_->PrintValue(bpt); }
   void AddValue(TokenPosition tp) const { stream_->PrintValue(tp); }
   void AddValue(const ServiceEvent* event) const { stream_->PrintValue(event); }