Fix client stats payload

Author: amarziali

dd-trace-core/src/main/java/datadog/trace/common/metrics/SerializingMetricWriter.java

@@ -12,8 +12,8 @@
 
 public final class SerializingMetricWriter implements MetricWriter {
 
-  private static final byte[] SEQUENCE = "Seq".getBytes(ISO_8859_1);
-  private static final byte[] RUNTIME_ID = "RuntimeId".getBytes(ISO_8859_1);
+  private static final byte[] SEQUENCE = "Sequence".getBytes(ISO_8859_1);
+  private static final byte[] RUNTIME_ID = "RuntimeID".getBytes(ISO_8859_1);
   private static final byte[] HOSTNAME = "Hostname".getBytes(ISO_8859_1);
   private static final byte[] NAME = "Name".getBytes(ISO_8859_1);
   private static final byte[] ENV = "Env".getBytes(ISO_8859_1);
@@ -61,7 +61,8 @@ public SerializingMetricWriter(WellKnownTags wellKnownTags, Sink sink, int initi
   public void startBucket(int metricCount, long start, long duration) {
     final UTF8BytesString processTags = ProcessTags.getTagsForSerialization();
     final boolean writeProcessTags = processTags != null;
-    writer.startMap(6 + (writeProcessTags ? 1 : 0));
+    writer.startMap(7 + (writeProcessTags ? 1 : 0));
+    System.err.println("Sending runtime ID " + wellKnownTags.getRuntimeId());
 
     writer.writeUTF8(RUNTIME_ID);
     writer.writeUTF8(wellKnownTags.getRuntimeId());
@@ -72,6 +73,9 @@ public void startBucket(int metricCount, long start, long duration) {
     writer.writeUTF8(HOSTNAME);
     writer.writeUTF8(wellKnownTags.getHostname());
 
+    writer.writeUTF8(SERVICE);
+    writer.writeUTF8(wellKnownTags.getService());
+
     writer.writeUTF8(ENV);
     writer.writeUTF8(wellKnownTags.getEnv());