about_flags::ReportCustomFlags() should use signed 32-bit IDs.

chrome/browser/about_flags.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 "chrome/browser/about_flags.h"
 
 #include <iterator>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 47 matching lines @@
 #endif
 
 #if defined(ENABLE_APP_LIST)
 #include "ui/app_list/app_list_switches.h"
 #endif
 
 using base::UserMetricsAction;
 
 namespace about_flags {
 
-const uint32_t kBadSwitchFormatHistogramId = 0;
+const int32_t kBadSwitchFormatHistogramId = 0;
 
 // Macros to simplify specifying the type.
 #define SINGLE_VALUE_TYPE_AND_VALUE(command_line_switch, switch_value) \
     Experiment::SINGLE_VALUE, \
     command_line_switch, switch_value, NULL, NULL, NULL, 0
 #define SINGLE_VALUE_TYPE(command_line_switch) \
     SINGLE_VALUE_TYPE_AND_VALUE(command_line_switch, "")
 #define ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(enable_switch, enable_value, \
                                             disable_switch, disable_value) \
     Experiment::ENABLE_DISABLE_VALUE, enable_switch, enable_value, \
@@ skipping 2152 matching lines @@
     action += *it;
     content::RecordComputedAction(action);
   }
   // Since flag metrics are recorded every startup, add a tick so that the
   // stats can be made meaningful.
   if (flags.size())
     content::RecordAction(UserMetricsAction("AboutFlags_StartupTick"));
   content::RecordAction(UserMetricsAction("StartupTick"));
 }
 
-uint32_t GetSwitchUMAId(const std::string& switch_name) {
-  return static_cast<uint32_t>(metrics::HashMetricName(switch_name));
+int32_t GetSwitchUMAId(const std::string& switch_name) {

[sky, 2014/08/28 23:27:29]

Shouldn't you use the same types as used by histogram, by which I mean a common
typedef?

[Alexander Alekseev, 2014/08/30 04:41:14]

Done.

+  return static_cast<int32_t>(metrics::HashMetricName(switch_name));
 }
 
 void ReportCustomFlags(const std::string& uma_histogram_hame,
                        const std::set<std::string>& command_line_difference) {
   for (std::set<std::string>::const_iterator it =
            command_line_difference.begin();
        it != command_line_difference.end();
        ++it) {
     int uma_id = about_flags::kBadSwitchFormatHistogramId;
     if (StartsWithASCII(*it, "--", true /* case_sensitive */)) {
@@ skipping 211 matching lines @@
 }
 
 const Experiment* GetExperiments(size_t* count) {
   *count = num_experiments;
   return experiments;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags