QUIC - disable QUIC if packet loss rate is bad for a connection.

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 4d36619ab5c661fca1ebe7526473152b376d5933..f1d692000f98b9e3b7c9eddf49f6a7ad93e4fc82 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -19791,6 +19791,14 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="Net.QuicStreamFactory.QuicIsDisabled">

[Mark P, 2015/03/26 20:21:42]

enum=?

[ramant (doing other things), 2015/03/26 21:03:35]

Added "Ports" enum. Does that sound reasonable. Generally we should see port 80
and 443 only. Will add as needed.

+  <owner>rtenneti@chromium.org</owner>
+  <summary>
+    Recorded whenever QUIC is disabled for a port due to high packet loss rate
+    and when number of lossy connections goes over a threshold.

[Mark P, 2015/03/26 20:21:42]

It might be good to say roughly how long this disabling lasts.  Until next
reboot of Chrome?  Permanently?  Until refresh of the page?

[Mark P, 2015/03/26 20:21:42]

I assume this is "or", not "and", right?

[ramant (doing other things), 2015/03/26 21:03:35]

Done.

[ramant (doing other things), 2015/03/26 21:03:35]

It is an and. We need to have high packet loss for 5 consecutive QUIC
handshakes. Then only we will disable.

+  </summary>
+</histogram>
+
 <histogram name="Net.QuicVerifyProofFailed.HandshakeConfirmed"
     enum="BooleanHandshakeConfirmed">
   <owner>rtenneti@chromium.org</owner>