[Mac] Add field trial tuples to breakpad crash reports.

chrome/common/metrics/experiments_helper.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/common/metrics/experiments_helper.h"
 
+#include <map>
 #include <vector>
 
 #include "base/memory/singleton.h"
 #include "base/sha1.h"
 #include "base/string16.h"
 #include "base/stringprintf.h"
 #include "base/sys_byteorder.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/common/child_process_logging.h"
 #include "chrome/common/metrics/variation_ids.h"
@@ skipping 106 matching lines @@
   GroupMapAccessor::GetInstance()->AssociateID(
       MakeSelectedGroupId(trial_name, group_name), id, true);
 }
 
 chrome_variations::ID GetGoogleVariationID(const std::string& trial_name,
                                            const std::string& group_name) {
   return GroupMapAccessor::GetInstance()->GetID(
       MakeSelectedGroupId(trial_name, group_name));
 }
 
+void GenerateExperimentChunks(const std::vector<string16>& experiments,
+                              std::vector<string16>* chunks) {
+  string16 current_chunk;
+  for (size_t i = 0; i < experiments.size(); ++i) {
+    const size_t needed_length =
+        (current_chunk.empty() ? 1 : 0) + experiments[i].length();
+    if (current_chunk.length() + needed_length > kMaxExperimentChunkSize) {
+      chunks->push_back(current_chunk);
+      current_chunk = experiments[i];
+    } else {
+      if (!current_chunk.empty())
+        current_chunk.push_back(',');
+      current_chunk += experiments[i];
+    }
+  }
+  if (!current_chunk.empty())
+    chunks->push_back(current_chunk);
+}
+
 void SetChildProcessLoggingExperimentList() {
   std::vector<SelectedGroupId> name_group_ids;
   GetFieldTrialSelectedGroupIds(&name_group_ids);
   std::vector<string16> experiment_strings(name_group_ids.size());
   for (size_t i = 0; i < name_group_ids.size(); ++i) {
     // Wish there was a StringPrintf for string16... :-(
     experiment_strings[i] = WideToUTF16(base::StringPrintf(
         L"%x-%x", name_group_ids[i].name, name_group_ids[i].group));
   }
   child_process_logging::SetExperimentList(experiment_strings);
@@ skipping 10 matching lines @@
     std::vector<experiments_helper::SelectedGroupId>* name_group_ids) {
   ::GetFieldTrialSelectedGroupIdsForSelectedGroups(selected_groups,
                                                    name_group_ids);
 }
 
 uint32 TestHashName(const std::string& name) {
   return ::HashName(name);
 }
 
 }  // namespace testing