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 db3356fd21c8b3f2c97f14929ce5fdd4acc12b81..ede63dcada48705fc87ddb3b46f80664128d07e6 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -19894,6 +19894,15 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="Net.QuicStreamFactory.QuicIsDisabled" enum="Ports">
+  <owner>rtenneti@chromium.org</owner>
+  <summary>
+    Recorded whenever QUIC is disabled for a port due to repeated lossy
+    connections (high packet loss on multiple consecutive connections). QUIC is
+    disabled until next reboot of Chrome.
+  </summary>
+</histogram>
+
 <histogram name="Net.QuicVerifyProofFailed.HandshakeConfirmed"
     enum="BooleanHandshakeConfirmed">
   <owner>rtenneti@chromium.org</owner>
@@ -57083,6 +57092,11 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="11" label="Bad Key Validation Signature"/>
 </enum>
 
+<enum name="Ports" type="int">
+  <int value="80" label="Port 80"/>
+  <int value="443" label="Port 443"/>
+</enum>
+
 <enum name="PostMergeVerificationOutcome" type="int">
   <int value="0" label="Undefined"/>
   <int value="1" label="Succeeded"/>