Domain Reliability: Add more upload-related histograms.

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 df61dd23653b4a56b7aead841dbd7f485b517af0..65a3408185ec23ef2be797da930a61aff22a5683 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -11127,6 +11127,22 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="DomainReliability.BeaconInterval" units="ms">
+  <owner>juliatuttle@chromium.org</owner>
+  <summary>
+    The time between successive Domain Reliability beacons being queued in the
+    same context. (Can be arbitrarily long if no beacons are queued in a while.)
+  </summary>
+</histogram>
+
+<histogram name="DomainReliability.BeaconIntervalGlobal" units="ms">
+  <owner>juliatuttle@chromium.org</owner>
+  <summary>
+    The time between successive Domain Reliability beacons being queued across
+    all contexts. (Can be arbitrarily long if no beacons are queued in a while.)
+  </summary>
+</histogram>
+
 <histogram name="DomainReliability.BeaconReported" enum="BooleanReported">
   <owner>juliatuttle@chromium.org</owner>
   <summary>
@@ -11160,6 +11176,25 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="DomainReliability.ReportedBeaconUploadDepth" units="levels">
+  <owner>juliatuttle@chromium.org</owner>
+  <summary>
+    The upload depth included in a beacon saved to be uploaded to the collector.
+    (Zero means the beacon was not about a report upload; n+1 means the beacon
+    was about a report with upload depth n.)
+  </summary>
+</histogram>
+
+<histogram name="DomainReliability.SetConfigRecreatedContext"
+    enum="BooleanCreated">
+  <owner>juliatuttle@chromium.org</owner>
+  <summary>
+    When Domain Reliability receives a valid NEL configuration header for an
+    origin with Domain Reliability active, whether or not it needed to recreate
+    the origin's context to apply a changed config.
+  </summary>
+</histogram>
+
 <histogram name="DomainReliability.UploadCollectorIndex">
   <owner>juliatuttle@chromium.org</owner>
   <summary>
@@ -11207,6 +11242,15 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="DomainReliability.UploadIntervalGlobal" units="ms">
+  <owner>juliatuttle@chromium.org</owner>
+  <summary>
+    The time between successive Domain Reliability uploads being started across
+    all contexts. (Can be arbitrarily long if no beacons are reported in a
+    while.)
+  </summary>
+</histogram>
+
 <histogram name="DomainReliability.UploadLatency" units="ms">
   <owner>juliatuttle@chromium.org</owner>
   <summary>