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

chromecast/media/cma/pipeline/audio_video_pipeline_impl_unittest.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 <memory>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 140 matching lines @@
   std::unique_ptr<CodedFrameProvider> CreateFrameProvider() {
     std::vector<FrameGeneratorForTest::FrameSpec> frame_specs;
     frame_specs.resize(kNumFrames);
     for (size_t k = 0; k < frame_specs.size() - 1; k++) {
       frame_specs[k].has_config = (k == 0);
       frame_specs[k].timestamp =
           base::TimeDelta::FromMicroseconds(kFrameDurationUs) * k;
       frame_specs[k].size = kFrameSize;
       frame_specs[k].has_decrypt_config = encrypted_;
     }
-    frame_specs[frame_specs.size() - 1].is_eos = true;
+    frame_specs.back().is_eos = true;
 
     std::unique_ptr<FrameGeneratorForTest> frame_generator(
         new FrameGeneratorForTest(frame_specs));
     bool provider_delayed_pattern[] = {false, true};
     std::unique_ptr<MockFrameProvider> frame_provider(new MockFrameProvider());
     frame_provider->Configure(
         std::vector<bool>(
             provider_delayed_pattern,
             provider_delayed_pattern + arraysize(provider_delayed_pattern)),
         std::move(frame_generator));
@@ skipping 193 matching lines @@
 
   message_loop_.RunUntilIdle();
   message_loop_.PostTask(FROM_HERE,
                          base::Bind(&PipelineHelper::SetCdmLicenseInstalled,
                                     base::Unretained(pipeline_helper_.get())));
   message_loop_.Run();
 }
 
 }  // namespace media
 }  // namespace chromecast