Fixup keepalive logic (closes #1274)

Spigot-Server-Patches/0215-revert-serverside-behavior-of-keepalives.patch

@@ -1,4 +1,4 @@
-From a4ee3c01cd5658dbf171d22af6b6fd271249375a Mon Sep 17 00:00:00 2001
+From 362e23402aaa442d707e2589f8541d39e4734a51 Mon Sep 17 00:00:00 2001
 From: Shane Freeder <theboyetronic@gmail.com>
 Date: Sun, 15 Oct 2017 00:29:07 +0100
 Subject: [PATCH] revert serverside behavior of keepalives
@@ -17,7 +17,7 @@ from networking or during connections flood of chunk packets on slower clients,
  at the cost of dead connections being kept open for longer.
 
 diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
-index add29081d2..cb9f25e961 100644
+index b106454447..60d9f5706a 100644
 --- a/src/main/java/net/minecraft/server/PlayerConnection.java
 +++ b/src/main/java/net/minecraft/server/PlayerConnection.java
 @@ -69,7 +69,7 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
@@ -25,7 +25,7 @@ index add29081d2..cb9f25e961 100644
      public EntityPlayer player;
      private int e;
 -    private long f; private void setLastPing(long lastPing) { this.f = lastPing;}; private long getLastPing() { return this.f;}; // Paper - OBFHELPER
-+    private long f = System.currentTimeMillis(); private void setLastPing(long lastPing) { this.f = lastPing;}; private long getLastPing() { return this.f;}; // Paper - OBFHELPER - set ping to delay initial
++    private long f = SystemUtils.b(); private void setLastPing(long lastPing) { this.f = lastPing;}; private long getLastPing() { return this.f;}; // Paper - OBFHELPER - set ping to delay initial
      private boolean g; private void setPendingPing(boolean isPending) { this.g = isPending;}; private boolean isPendingPing() { return this.g;}; // Paper - OBFHELPER
      private long h; private void setKeepAliveID(long keepAliveID) { this.h = keepAliveID;}; private long getKeepAliveID() {return this.h; };  // Paper - OBFHELPER
      // CraftBukkit start - multithreaded fields