Add Net.WebSocket.ResponseCode and ErrorCodes UMA

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 4018f9a8497678158cda945d67382921b8f27cea..461dd2e09dfba9f709df611498d23013ce479e7f 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -15451,6 +15451,15 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="Net.WebSocket.ErrorCodes" enum="NetErrorCodes">
+  <owner>yhirano@chromium.org</owner>
+  <owner>ricea@chromium.org</owner>
+  <owner>tyoshino@chromium.org</owner>
+  <summary>
+    Positive net error codes that WebSockets end with, including OK and ABORTED.
+  </summary>
+</histogram>
+
 <histogram name="Net.WebSocket.HandshakeResult"
     enum="WebSocketNewHandshakeResult">
   <owner>yhirano@chromium.org</owner>
@@ -15462,6 +15471,13 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="Net.WebSocket.ResponseCode">

[Alexei Svitkine (slow), 2014/06/17 15:34:27]

enum="HttpResponseCode"

[Adam Rice, 2014/06/18 01:23:19]

Done.

+  <owner>yhirano@chromium.org</owner>
+  <owner>ricea@chromium.org</owner>
+  <owner>tyoshino@chromium.org</owner>
+  <summary>All HTTP status codes seen during WebSocket handshakes.</summary>
+</histogram>
+
 <histogram name="Net.Wifi.InterfaceCount">
   <owner>mvanouwerkerk@chromium.org</owner>
   <summary>