Mac: Make ScopedTypeRef require explicit constructors

chrome/browser/ui/cocoa/fullscreen_low_power_coordinator.h

 // Copyright 2016 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.
 
 #ifndef CHROME_BROWSER_UI_COCOA_FULLSCREEN_LOW_POWER_COORDINATOR_H_
 #define CHROME_BROWSER_UI_COCOA_FULLSCREEN_LOW_POWER_COORDINATOR_H_
 
 #include "ui/accelerated_widget_mac/accelerated_widget_mac.h"
 #include "ui/accelerated_widget_mac/fullscreen_low_power_coordinator.h"
 
@@ skipping 26 matching lines @@
   // ui::FullscreenLowPowerCoordinator implementation.
   void SetLowPowerLayerValid(bool valid) override;
   void WillLoseAcceleratedWidget() override;
 
  private:
   // Determine if we should be fullscreen low power mode, and enter or exit
   // the mode as needed.
   void EnterOrExitLowPowerModeIfNeeded();
 
   // The main fullscreen window.
-  base::scoped_nsobject<NSWindow> content_window_ = nil;
+  base::scoped_nsobject<NSWindow> content_window_;
 
   // Weak, reset by WillLoseAcceleratedWidget before it goes away.
   ui::AcceleratedWidgetMac* widget_ = nullptr;
 
   // The window that we will put in front of the main fullscreen window when we
   // can.
   base::scoped_nsobject<FullscreenLowPowerWindow> low_power_window_;
 
   // Set by the AcceleratedWidgetHost with each frame. This must be true to
   // enter low power mode.
   bool low_power_layer_valid_ = false;
 
   // Set if the NSView hierarchy allows low power mode. Low power mode is only
   // allowed when nothing but the web contents is on-screen.
   bool allowed_by_nsview_layout_ = true;
 
   // Updated by EnterOrExitLowPowerModeIfNeeded.
   bool in_low_power_mode_ = false;
 };
 
 #endif  // CHROME_BROWSER_UI_COCOA_FULLSCREEN_LOW_POWER_COORDINATOR_H_