Use container::back() and container::pop_back() in ui/

ui/base/win/open_file_name_win_unittest.cc

 // Copyright (c) 2014 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 "ui/base/win/open_file_name_win.h"
 
 #include <stddef.h>
 
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 const HWND kHwnd = reinterpret_cast<HWND>(0xDEADBEEF);
 const DWORD kFlags = OFN_OVERWRITEPROMPT | OFN_EXPLORER | OFN_ENABLESIZING;
 
 void SetResult(const base::string16& result, ui::win::OpenFileName* ofn) {
   if (ofn->GetOPENFILENAME()->nMaxFile <= result.size()) {
     ADD_FAILURE() << "filename buffer insufficient.";
     return;
   }
-  if (!result.size()) {
+  if (result.empty()) {
     ofn->GetOPENFILENAME()->lpstrFile[0] = 0;
   } else {
     // Because the result has embedded nulls, we must memcpy.
     memcpy(ofn->GetOPENFILENAME()->lpstrFile,
            result.c_str(),
            (result.size() + 1) * sizeof(result[0]));
   }
 }
 
 void CheckFilters(
@@ skipping 214 matching lines @@
   ui::win::OpenFileName::SetResult(directory, filenames, ofn.GetOPENFILENAME());
   CheckResult(L"C:\\dir" + kNull + L"file" + kNull + L"otherfile" + kNull, ofn);
 
   base::char16 short_buffer[10] = L"";
 
   ofn.GetOPENFILENAME()->lpstrFile = short_buffer;
   ofn.GetOPENFILENAME()->nMaxFile = arraysize(short_buffer);
   ui::win::OpenFileName::SetResult(directory, filenames, ofn.GetOPENFILENAME());
   CheckResult(L"", ofn);
 }