Fix up certificate error reporting histograms

net/http/transport_security_state.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/http/transport_security_state.h"
 
 #include <algorithm>
 #include <memory>
 #include <utility>
 #include <vector>
@@ skipping 31 matching lines @@
 const size_t kReportCacheKeyLength = 16;
 
 // Override for ShouldRequireCT() for unit tests. Possible values:
 //  -1: Unless a delegate says otherwise, do not require CT.
 //   0: Use the default implementation (e.g. production)
 //   1: Unless a delegate says otherwise, require CT.
 int g_ct_required_for_testing = 0;
 
 void RecordUMAForHPKPReportFailure(const GURL& report_uri, int net_error) {
   UMA_HISTOGRAM_SPARSE_SLOWLY("Net.PublicKeyPinReportSendingFailure",
-                              net_error);
+                              -net_error);
 }
 
 std::string TimeToISO8601(const base::Time& t) {
   base::Time::Exploded exploded;
   t.UTCExplode(&exploded);
   return base::StringPrintf(
       "%04d-%02d-%02dT%02d:%02d:%02d.%03dZ", exploded.year, exploded.month,
       exploded.day_of_month, exploded.hour, exploded.minute, exploded.second,
       exploded.millisecond);
 }
@@ skipping 1373 matching lines @@
 TransportSecurityState::PKPStateIterator::PKPStateIterator(
     const TransportSecurityState& state)
     : iterator_(state.enabled_pkp_hosts_.begin()),
       end_(state.enabled_pkp_hosts_.end()) {
 }
 
 TransportSecurityState::PKPStateIterator::~PKPStateIterator() {
 }
 
 }  // namespace