Add presubmit check for scoped_ptr usage.

ui/ozone/platform/dri/hardware_display_controller.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 "ui/ozone/platform/dri/hardware_display_controller.h"
 
 #include <drm.h>
 #include <errno.h>
 #include <string.h>
 #include <xf86drm.h>
@@ skipping 167 matching lines @@
       // If a display configuration happens mid page flip we want to make sure
       // the HDC won't wait for an event from a CRTC that is no longer
       // associated with it.
       if (controller->page_flip_pending())
         OnPageFlipEvent();
 
       return controller.Pass();
     }
   }
 
-  return scoped_ptr<CrtcController>();
+  return nullptr;
 }
 
 bool HardwareDisplayController::HasCrtc(uint32_t crtc) const {
   for (size_t i = 0; i < crtc_controllers_.size(); ++i)
     if (crtc_controllers_[i]->crtc() == crtc)
       return true;
 
   return false;
 }
 
@@ skipping 106 matching lines @@
 
 void HardwareDisplayController::ClearPendingRequests() {
   while (!requests_.empty()) {
     PageFlipRequest request = requests_.front();
     requests_.pop_front();
     request.callback.Run();
   }
 }
 
 }  // namespace ui