Use container::back() and container::pop_back().

gpu/command_buffer/service/program_manager.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 "gpu/command_buffer/service/program_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 41 matching lines @@
   }
 }
 
 // Given a name like "foo.bar[123].moo[456]" sets new_name to "foo.bar[123].moo"
 // and sets element_index to 456. returns false if element expression was not a
 // whole decimal number. For example: "foo[1b2]"
 bool GetUniformNameSansElement(
     const std::string& name, int* element_index, std::string* new_name) {
   DCHECK(element_index);
   DCHECK(new_name);
-  if (name.size() < 3 || name[name.size() - 1] != ']') {
+  if (name.size() < 3 || name.back() != ']') {
     *element_index = 0;
     *new_name = name;
     return true;
   }
 
   // Look for an array specification.
   size_t open_pos = name.find_last_of('[');
   if (open_pos == std::string::npos ||
       open_pos >= name.size() - 2) {
     return false;
@@ skipping 1569 matching lines @@
         return true;
       }
       continue;
     }
 
     if (!hit->second.isSameVaryingAtLinkTime(key_value.second,
                                              shader_version)) {
       *conflicting_name = name;
       return true;
     }
-
   }
   return false;
 }
 
 bool Program::DetectFragmentInputLocationBindingConflicts() const {
   auto shader = attached_shaders_[ShaderTypeToIndex(GL_FRAGMENT_SHADER)].get();
   if (!shader || !shader->valid())
     return false;
 
   std::set<GLint> location_binding_used;
@@ skipping 704 matching lines @@
   DCHECK(program);
   program->ClearUniforms(&zero_);
 }
 
 int32_t ProgramManager::MakeFakeLocation(int32_t index, int32_t element) {
   return index + element * 0x10000;
 }
 
 }  // namespace gles2
 }  // namespace gpu