Enable clang style plugin in webrtc/modules/desktop_capture

webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.h

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 22 matching lines @@
 // duplicator or not. If a previous IsSupported() function call returns true,
 // but a later Duplicate() returns false, this usually means the display mode is
 // changing. Consumers should retry after a while. (Typically 50 milliseconds,
 // but according to hardware performance, this time may vary.)
 class DxgiDuplicatorController {
  public:
   // A context to store the status of a single consumer of
   // DxgiDuplicatorController.
   class Context {
    public:
+    Context();
     // Unregister this Context instance from all Dxgi duplicators during
     // destructing.
     ~Context();
 
    private:
     friend class DxgiDuplicatorController;
 
     // A Context will have an exactly same |identity_| as
     // DxgiDuplicatorController, to ensure it has been correctly setted up after
     // each DxgiDuplicatorController::Initialize().
@@ skipping 97 matching lines @@
   // ensure a Context has been initialized after DxgiDuplicatorController.
   int identity_ = 0;
   DesktopRect desktop_rect_;
   DesktopVector dpi_;
   std::vector<DxgiAdapterDuplicator> duplicators_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_DXGI_DUPLICATOR_CONTROLLER_H_