Add RelatedEventSet Diagnostic

tracing/tracing/model/model.html

Index: tracing/tracing/model/model.html
diff --git a/tracing/tracing/model/model.html b/tracing/tracing/model/model.html
index dbc4e2cc62a51149b5e1e67da1063688849ee0e0..b47840a5d9e0e72f25f3845c4e19b8b305a8ebb7 100644
--- a/tracing/tracing/model/model.html
+++ b/tracing/tracing/model/model.html
@@ -110,11 +110,22 @@ tr.exportTo('tr', function() {
 
     this.doesHelperGUIDSupportThisModel_ = {};
     this.helpersByConstructorGUID_ = {};
+    this.eventsByStableId_ = undefined;
   }
 
   Model.prototype = {
     __proto__: tr.model.EventContainer.prototype,
 
+    getEventByStableId: function(stableId) {
+      if (this.eventsByStableId_ === undefined) {
+        this.eventsByStableId_ = {};
+        this.iterateAllEvents(function(event) {
+          this.eventsByStableId_[event.stableId] = event;
+        }, this);
+      }
+      return this.eventsByStableId_[stableId];
+    },
+
     getOrCreateHelper: function(constructor) {
       if (!constructor.guid)
         throw new Error('Helper constructors must have GUIDs');