Domain Reliability: Add sample_rate field to Beacon

components/domain_reliability/beacon.h

Index: components/domain_reliability/beacon.h
diff --git a/components/domain_reliability/beacon.h b/components/domain_reliability/beacon.h
index f3a56c9b3a359830ac1a4aa5cd79bd9366b4a7c3..5c61c2ad7c574690a8b8b96898d310485f96dca2 100644
--- a/components/domain_reliability/beacon.h
+++ b/components/domain_reliability/beacon.h
@@ -65,6 +65,9 @@ struct DOMAIN_RELIABILITY_EXPORT DomainReliabilityBeacon {
   // caused by an upload that itself contained no beacons caused by uploads,
   // et cetera.
   int upload_depth;
+  // "Weight" of this beacon -- the inverse of the sampling rate under which it
+  // was chosen to be reported.

[jkarlin, 2015/12/07 14:57:27]

Why inverse? Why not just report the sampling rate? 

[Deprecated (see juliatuttle), 2015/12/07 20:17:57]

Done.

+  int weight;

[jkarlin, 2015/12/07 14:57:27]

Why an int? You're losing significant data here.

[Deprecated (see juliatuttle), 2015/12/07 20:17:57]

In our own tests, we've only ever used things (other than 100%) like 5% or 10%.

[jkarlin, 2015/12/08 19:41:36]

But the sample_rate is a double in the range [0,1] right?

 
   // Okay to copy and assign.
 };