Replace GetAllErrorCodesForUma calls with UMA_HISTOGRAM_SPARSE_SLOWLY.

net/dns/host_resolver_impl.cc

Index: net/dns/host_resolver_impl.cc
diff --git a/net/dns/host_resolver_impl.cc b/net/dns/host_resolver_impl.cc
index bd6e43198dca94319fe32227f5bc89475634f90a..d3b62d2d8ad1b556b6a38f2b3bf2b257c9be4832 100644
--- a/net/dns/host_resolver_impl.cc
+++ b/net/dns/host_resolver_impl.cc
@@ -24,6 +24,7 @@
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"

[Alexei Svitkine (slow), 2015/05/15 20:38:28]

Ditto.

[davidben, 2015/05/15 20:41:01]

Done.

+#include "base/metrics/sparse_histogram.h"
 #include "base/profiler/scoped_tracker.h"
 #include "base/stl_util.h"
 #include "base/strings/string_util.h"
@@ -1535,9 +1536,8 @@ class HostResolverImpl::Job : public PrioritizedDispatcher::Job,
         } else {
           UmaAsyncDnsResolveStatus(RESOLVE_STATUS_PROC_SUCCESS);
         }
-        UMA_HISTOGRAM_CUSTOM_ENUMERATION("AsyncDNS.ResolveError",
-                                         std::abs(dns_task_error_),
-                                         GetAllErrorCodesForUma());
+        UMA_HISTOGRAM_SPARSE_SLOWLY("AsyncDNS.ResolveError",
+                                    std::abs(dns_task_error_));
         resolver_->OnDnsTaskResolve(dns_task_error_);
       } else {
         DNS_HISTOGRAM("AsyncDNS.FallbackFail", duration);
@@ -2376,9 +2376,8 @@ void HostResolverImpl::OnDnsTaskResolve(int net_error) {
   AbortDnsTasks();
 
   UMA_HISTOGRAM_BOOLEAN("AsyncDNS.DnsClientEnabled", false);
-  UMA_HISTOGRAM_CUSTOM_ENUMERATION("AsyncDNS.DnsClientDisabledReason",
-                                   std::abs(net_error),
-                                   GetAllErrorCodesForUma());
+  UMA_HISTOGRAM_SPARSE_SLOWLY("AsyncDNS.DnsClientDisabledReason",
+                              std::abs(net_error));
 }
 
 void HostResolverImpl::SetDnsClient(scoped_ptr<DnsClient> dns_client) {