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

ui/views/layout/grid_layout.cc

Index: ui/views/layout/grid_layout.cc
diff --git a/ui/views/layout/grid_layout.cc b/ui/views/layout/grid_layout.cc
index c79b600ffef0e0c3dceab36b94e17625820c06e7..438d376415b8d249e9bbd7a89b19bd4fadbb958e 100644
--- a/ui/views/layout/grid_layout.cc
+++ b/ui/views/layout/grid_layout.cc
@@ -937,8 +937,8 @@ void GridLayout::SizeRowsAndColumns(bool layout, int width, int height,
   LayoutElement::CalculateLocationsFromSize(&rows_);
 
   // We now know the preferred height, set it here.
-  pref->set_height(rows_[rows_.size() - 1]->Location() +
-      rows_[rows_.size() - 1]->Size() + insets_.height());
+  pref->set_height(rows_.back()->Location() + rows_.back()->Size() +
+                   insets_.height());
 
   if (layout && height != pref->height()) {
     // We're doing a layout, and the height differs from the preferred height,