Don't spam warnings when Mojang's API goes down. (Which happens a lot)

CraftBukkit-Patches/0129-Convert-player-heads-async.patch

@@ -1,4 +1,4 @@
-From d303eb8ffc3f82badc690c1bad71782f0d5f7b57 Mon Sep 17 00:00:00 2001
+From 2734342f54016d2ca4440bd07ed371a6458f5ccc Mon Sep 17 00:00:00 2001
 From: Thinkofdeath <thethinkofdeath@gmail.com>
 Date: Wed, 9 Apr 2014 13:29:57 +0100
 Subject: [PATCH] Convert player heads async
@@ -112,10 +112,10 @@ index b241cfe..925e017 100644
      public Packet getUpdatePacket() {
 diff --git a/src/main/java/org/spigotmc/HeadConverter.java b/src/main/java/org/spigotmc/HeadConverter.java
 new file mode 100644
-index 0000000..bc949a1
+index 0000000..a284768
 --- /dev/null
 +++ b/src/main/java/org/spigotmc/HeadConverter.java
-@@ -0,0 +1,163 @@
+@@ -0,0 +1,168 @@
 +package org.spigotmc;
 +
 +import com.google.common.base.Charsets;
@@ -148,6 +148,7 @@ index 0000000..bc949a1
 +                    .setNameFormat( "Head Conversion Thread - %1$d" )
 +                    .build()
 +    );
++    private static boolean hasWarned = false;
 +
 +    public static void convertHead(final TileEntitySkull head)
 +    {
@@ -267,7 +268,11 @@ index 0000000..bc949a1
 +                    e.printStackTrace();
 +                } catch ( IOException e )
 +                {
++                    if (!hasWarned)
++                    {
++                        hasWarned = true;
 +                        Bukkit.getLogger().warning( "Error connecting to Mojang servers, cannot convert player heads" );
++                    }
 +                } finally
 +                {
 +                    if ( connection != null )