Remove base::Value::CreateNullValue

extensions/browser/app_window/app_window.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 "extensions/browser/app_window/app_window.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <string>
@@ skipping 63 matching lines @@
 
 const int kDefaultWidth = 512;
 const int kDefaultHeight = 384;
 
 void SetConstraintProperty(const std::string& name,
                            int value,
                            base::DictionaryValue* bounds_properties) {
   if (value != SizeConstraints::kUnboundedSize)
     bounds_properties->SetInteger(name, value);
   else
-    bounds_properties->Set(name, base::Value::CreateNullValue());
+    bounds_properties->Set(name, base::MakeUnique<base::Value>());
 }
 
 void SetBoundsProperties(const gfx::Rect& bounds,
                          const gfx::Size& min_size,
                          const gfx::Size& max_size,
                          const std::string& bounds_name,
                          base::DictionaryValue* window_properties) {
   std::unique_ptr<base::DictionaryValue> bounds_properties(
       new base::DictionaryValue());
 
@@ skipping 1018 matching lines @@
         region.bounds.x(),
         region.bounds.y(),
         region.bounds.right(),
         region.bounds.bottom(),
         region.draggable ? SkRegion::kUnion_Op : SkRegion::kDifference_Op);
   }
   return sk_region;
 }
 
 }  // namespace extensions