Fix follow-up in webrtc/test/field_trial.cc.

webrtc/test/field_trial.cc

 /*
  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 28 matching lines @@
 }
 }  // namespace field_trial
 
 namespace test {
 // Note: this code is copied from src/base/metrics/field_trial.cc since the aim
 // is to mimic chromium --force-fieldtrials.
 void InitFieldTrialsFromString(const std::string& trials_string) {
   static const char kPersistentStringSeparator = '/';
 
   // Catch an error if this is called more than once.
-  assert(field_trials_initiated_ == false);
+  assert(!field_trials_initiated_);
   field_trials_initiated_ = true;
 
   if (trials_string.empty())
     return;
 
   size_t next_item = 0;
   while (next_item < trials_string.length()) {
     size_t name_end = trials_string.find(kPersistentStringSeparator, next_item);
     if (name_end == trials_string.npos || next_item == name_end)
       break;
@@ skipping 10 matching lines @@
     if (field_trials_.find(name) != field_trials_.end() &&
         field_trials_.find(name)->second != group_name)
       break;
 
     field_trials_[name] = group_name;
 
     // Successfully parsed all field trials from the string.
     if (next_item == trials_string.length())
       return;
   }
-  // LOG does not prints when this is called early on main.
+  // Using fprintf as LOG does not print when this is called early in main.
   fprintf(stderr, "Invalid field trials string.\n");
 
-  // Using abort so it crashs both in debug and release mode.
+  // Using abort so it crashes in both debug and release mode.
   abort();
 }
 
 ScopedFieldTrials::ScopedFieldTrials(const std::string& config)
     : previous_field_trials_(field_trials_) {
   assert(field_trials_initiated_);
   field_trials_initiated_ = false;
-  field_trials_ = std::map<std::string, std::string>();
+  field_trials_.clear();
   InitFieldTrialsFromString(config);
 }
 
 ScopedFieldTrials::~ScopedFieldTrials() {
+  // Should still be initialized, since InitFieldTrials is called from ctor.
+  // That's why we don't restore the flag.
+  assert(field_trials_initiated_);
   field_trials_ = previous_field_trials_;
 }
 
 }  // namespace test
 }  // namespace webrtc