Reland of place string::find(prefix) == 0 pattern with base::StartsWith().

chromeos/settings/timezone_settings.cc

 // Copyright 2013 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 "chromeos/settings/timezone_settings.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <string>
@@ skipping 205 matching lines @@
   const ssize_t len = readlink(kTimezoneSymlink, buf,
                                sizeof(buf)-1);
   if (len == -1) {
     LOG(ERROR) << "GetTimezoneID: Cannot read timezone symlink "
                << kTimezoneSymlink;
     return std::string();
   }
 
   std::string timezone(buf, len);
   // Remove kTimezoneFilesDir from the beginning.
-  if (timezone.find(kTimezoneFilesDir) != 0) {
+  if (!base::StartsWith(timezone, kTimezoneFilesDir,
+                        base::CompareCase::SENSITIVE)) {
     LOG(ERROR) << "GetTimezoneID: Timezone symlink is wrong "
                << timezone;
     return std::string();
   }
 
   return timezone.substr(strlen(kTimezoneFilesDir));
 }
 
 void SetTimezoneIDFromString(const std::string& id) {
   // Change the kTimezoneSymlink symlink to the path for this timezone.
@@ skipping 237 matching lines @@
 
 // static
 base::string16 TimezoneSettings::GetTimezoneID(const icu::TimeZone& timezone) {
   icu::UnicodeString id;
   timezone.getID(id);
   return base::string16(id.getBuffer(), id.length());
 }
 
 }  // namespace system
 }  // namespace chromeos