Create a mechanism for reporting rappor metrics from non-UMA

components/rappor/rappor_parameters.h

Index: components/rappor/rappor_parameters.h
diff --git a/components/rappor/rappor_parameters.h b/components/rappor/rappor_parameters.h
index ca625ba4d8e3216969d5efe2b545aabb91878029..cc07e2f19c8079fe6af2aae7c2678542a4f30c89 100644
--- a/components/rappor/rappor_parameters.h
+++ b/components/rappor/rappor_parameters.h
@@ -27,6 +27,8 @@ struct RapporParameters {
   static const int kMaxCohorts;
 
   // The number of cohorts to divide the reports for this metric into.
+  // This should divide kMaxCohorts evenly so that each cohort has an equal
+  // probability of being assigned users.
   int num_cohorts;
 
   // The number of bytes stored in the Bloom filter.
@@ -43,6 +45,9 @@ struct RapporParameters {
   Probability one_coin_prob;
   // The probability that a zero bit in the redacted data reports as one.
   Probability zero_coin_prob;
+
+  // When true, this metric will be reported by the full population of users.
+  bool always_enabled;
 };
 
 }  // namespace rappor