use a single, shared timestamps array between all pings

lib/servers.js

@@ -16,7 +16,7 @@ class ServerRegistration {
 
   handlePing (timestamp, resp, err, version) {
     // Store into in-memory ping data
-    this.addPing(timestamp, resp)
+    this.addPing(resp)
 
     // Only notify the frontend to append to the historical graph
     // if both the graphing behavior is enabled and the backend agrees
@@ -89,10 +89,8 @@ class ServerRegistration {
     return update
   }
 
-  addPing (timestamp, resp) {
-    const ping = {
-      timestamp: timestamp
-    }
+  addPing (resp) {
+    const ping = {}
 
     if (resp) {
       // Append a result object
@@ -127,7 +125,6 @@ class ServerRegistration {
 
       const payload = {
         serverId: this.serverId,
-        timestamp: lastPing.timestamp,
         versions: this.versions,
         recordData: this.recordData,
         favicon: this.lastFavicon
@@ -157,7 +154,6 @@ class ServerRegistration {
 
     return [{
       serverId: this.serverId,
-      timestamp: new Date().getTime(),
       error: {
         message: 'Waiting...',
         placeholder: true