Use a direct include of strings headers in chrome/browser/a*-c*/.

chrome/browser/chrome_browser_field_trials.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/chrome_browser_field_trials.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
 #include "base/prefs/pref_service.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/time.h"
 #include "chrome/browser/omnibox/omnibox_field_trial.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/metrics/variations/uniformity_field_trials.h"
 #include "chrome/common/pref_names.h"
 
 #if defined(OS_ANDROID) || defined(OS_IOS)
 #include "chrome/browser/chrome_browser_field_trials_mobile.h"
 #else
@@ skipping 30 matching lines @@
   // Call |FindValue()| on the trials below, which may come from the server, to
   // ensure they get marked as "used" for the purposes of data reporting.
   base::FieldTrialList::FindValue("UMA-Dynamic-Binary-Uniformity-Trial");
   base::FieldTrialList::FindValue("UMA-Dynamic-Uniformity-Trial");
   base::FieldTrialList::FindValue("InstantDummy");
   base::FieldTrialList::FindValue("InstantChannel");
   base::FieldTrialList::FindValue("Test0PercentDefault");
   // Activate the autocomplete dynamic field trials.
   OmniboxFieldTrial::ActivateDynamicTrials();
 }