Change other usages of .size() to .empty() when applicable.

chrome/browser/chromeos/login/wizard_accessibility_handler.cc

 // Copyright (c) 2011 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/chromeos/login/wizard_accessibility_handler.h"
 
 #include <algorithm>
 
 #include "base/i18n/char_iterator.h"
 #include "base/logging.h"
@@ skipping 412 matching lines @@
       old_indices[prefix_char_len],
       old_indices[old_suffix_char_start] - old_indices[prefix_char_len]);
 
   // Find the substring that was inserted (if any) to get the new string
   // from the old - it's the part in the middle of the new string if you
   // remove the common prefix and suffix.
   std::string inserted = new_value.substr(
       new_indices[prefix_char_len],
       new_indices[new_suffix_char_start] - new_indices[prefix_char_len]);
 
-  if (inserted.size() > 0 && deleted.size() > 0) {
+  if (!inserted.empty() && !deleted.empty()) {
     // Replace one substring with another, speak inserted text.
     AppendUtterance(inserted, out_spoken_description);
-  } else if (inserted.size() > 0) {
+  } else if (!inserted.empty()) {
     // Speak inserted text.
     AppendUtterance(inserted, out_spoken_description);
-  } else if (deleted.size() > 0) {
+  } else if (!deleted.empty()) {
     // Speak deleted text.
     AppendUtterance(deleted, out_spoken_description);
   }
 }
 
 }  // namespace chromeos