Add and implement API to associate Google experiment IDs with FieldTrials.

base/metrics/field_trial.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 "base/metrics/field_trial.h"
 
 #include "base/build_time.h"
 #include "base/logging.h"
 #include "base/rand_util.h"
 #include "base/sha1.h"
@@ skipping 149 matching lines @@
 
 // static
 std::string FieldTrial::MakeName(const std::string& name_prefix,
                                  const std::string& trial_name) {
   std::string big_string(name_prefix);
   big_string.append(1, kHistogramFieldTrialSeparator);
   return big_string.append(FieldTrialList::FindFullName(trial_name));
 }
 
 // static
+FieldTrial::NameGroupId FieldTrial::MakeNameGroupId(
+    const std::string& trial_name,
+    const std::string& group_name) {
+  NameGroupId id;
+  id.name = HashName(trial_name);
+  id.group = HashName(group_name);
+  return id;
+}
+
+// static
 void FieldTrial::EnableBenchmarking() {
   DCHECK_EQ(0u, FieldTrialList::GetFieldTrialCount());
   enable_benchmarking_ = true;
 }
 
 FieldTrial::~FieldTrial() {}
 
 void FieldTrial::SetGroupChoice(const std::string& name, int number) {
   group_ = number;
   if (name.empty())
@@ skipping 296 matching lines @@
     used_without_global_ = true;
     return;
   }
   AutoLock auto_lock(global_->lock_);
   DCHECK(!global_->PreLockedFind(trial->name()));
   trial->AddRef();
   global_->registered_[trial->name()] = trial;
 }
 
 }  // namespace base