Re-write many calls to WrapUnique() with MakeUnique()

ash/wm/window_mirror_view.cc

Index: ash/wm/window_mirror_view.cc
diff --git a/ash/wm/window_mirror_view.cc b/ash/wm/window_mirror_view.cc
index 374207c1c61cc35bec7ca4d259119404fcc4ffd2..77115a7426d118b53bdabcf69ae61002cc2f27c0 100644
--- a/ash/wm/window_mirror_view.cc
+++ b/ash/wm/window_mirror_view.cc
@@ -74,7 +74,7 @@ ui::LayerDelegate* WindowMirrorView::CreateDelegate(
   if (!delegate)
     return nullptr;
   delegates_.push_back(
-      base::WrapUnique(new ForwardingLayerDelegate(target_, delegate)));
+      base::MakeUnique<ForwardingLayerDelegate>(target_, delegate));
 
   return delegates_.back().get();
 }