[Telemetry] Listen for mutation

Listen for mutation from telemetry subscriptions,
WTD-1329.

platform/telemetry/src/TelemetrySubscription.js

@@ -59,6 +59,7 @@ define(
                 telemetryObjects = [],
                 pool = lossless ? new TelemetryQueue() : new TelemetryTable(),
                 metadatas,
+                unlistenToMutation,
                 updatePending;
 
             // Look up domain objects which have telemetry capabilities.
@@ -153,6 +154,7 @@ define(
                 return objects;
             }
 
+            function initialize() {
                 // Get a reference to relevant objects (those with telemetry
                 // capabilities) and subscribe to their telemetry updates.
                 // Keep a reference to their promised return values, as these
@@ -163,6 +165,30 @@ define(
                 unsubscribePromise = telemetryObjectPromise
                         .then(cacheObjectReferences)
                         .then(subscribeAll);
+            }
+
+            function idsMatch(ids) {
+                return ids.every(function (id, index) {
+                    return telemetryObjects[index].getId() === id;
+                });
+            }
+
+            function modelChange(model) {
+                if (!idsMatch((model || {}).composition || [])) {
+                    // Reinitialize if composition has changed
+                    initialize();
+                }
+            }
+
+            function addMutationListener() {
+                var mutation = domainObject.getCapability('mutation');
+                if (mutation) {
+                    return mutation.listen(modelChange);
+                }
+            }
+
+            initialize();
+            unlistenToMutation = addMutationListener();
 
             return {
                 /**
@@ -172,6 +198,9 @@ define(
                  * @memberof TelemetrySubscription
                  */
                 unsubscribe: function () {
+                    if (unlistenToMutation) {
+                        unlistenToMutation();
+                    }
                     return unsubscribePromise.then(function (unsubscribes) {
                         return $q.all(unsubscribes.map(function (unsubscribe) {
                             return unsubscribe();