WTF/std normalization: replace WTF::Vector::last with ::back

third_party/WebKit/Source/platform/graphics/PictureSnapshot.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 161 matching lines @@
   const SkIRect bounds = m_picture->cullRect().roundOut();
   SkBitmap bitmap;
   bitmap.allocPixels(
       SkImageInfo::MakeN32Premul(bounds.width(), bounds.height()));
   bitmap.eraseARGB(0, 0, 0, 0);
 
   double now = WTF::monotonicallyIncreasingTime();
   double stopTime = now + minDuration;
   for (unsigned step = 0; step < minRepeatCount || now < stopTime; ++step) {
     timings->append(Vector<double>());
-    Vector<double>* currentTimings = &timings->last();
+    Vector<double>* currentTimings = &timings->back();
     if (timings->size() > 1)
       currentTimings->reserveCapacity(timings->begin()->size());
     ProfilingCanvas canvas(bitmap);
     if (clipRect) {
       canvas.clipRect(SkRect::MakeXYWH(clipRect->x(), clipRect->y(),
                                        clipRect->width(), clipRect->height()));
       canvas.resetStepCount();
     }
     canvas.setTimings(currentTimings);
     m_picture->playback(&canvas);
     now = WTF::monotonicallyIncreasingTime();
   }
   return timings;
 }
 
 std::unique_ptr<JSONArray> PictureSnapshot::snapshotCommandLog() const {
   const SkIRect bounds = m_picture->cullRect().roundOut();
   LoggingCanvas canvas(bounds.width(), bounds.height());
   m_picture->playback(&canvas);
   return canvas.log();
 }
 
 }  // namespace blink