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

ui/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.cc

 // Copyright 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/events/ozone/evdev/libgestures_glue/event_reader_libevdev_cros.h"
 
 #include <errno.h>
 #include <libevdev/libevdev.h>
 #include <linux/input.h>
 #include <utility>
 
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event.h"
 
 namespace ui {
 
 namespace {
 
 std::string FormatLog(const char* fmt, va_list args) {
   std::string msg = base::StringPrintV(fmt, args);
-  if (!msg.empty() && msg[msg.size() - 1] == '\n')
-    msg.erase(msg.end() - 1, msg.end());
+  if (!msg.empty() && msg.back() == '\n')
+    msg.pop_back();
   return msg;
 }
 
 }  // namespace
 
 EventReaderLibevdevCros::EventReaderLibevdevCros(
     int fd,
     const base::FilePath& path,
     int id,
     const EventDeviceInfo& devinfo,
@@ skipping 92 matching lines @@
   if (level >= LOGLEVEL_ERROR)
     LOG(ERROR) << "libevdev: " << FormatLog(fmt, args);
   else if (level >= LOGLEVEL_WARNING)
     LOG(WARNING) << "libevdev: " << FormatLog(fmt, args);
   else
     VLOG(3) << "libevdev: " << FormatLog(fmt, args);
   va_end(args);
 }
 
 }  // namespace ui