Use std::unique_ptr<> to pass frame ownership in DesktopCapturer impls.

webrtc/modules/desktop_capture/desktop_and_cursor_composer.h

 /*
  *  Copyright (c) 2013 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 24 matching lines @@
 
   // DesktopCapturer interface.
   void Start(DesktopCapturer::Callback* callback) override;
   void SetSharedMemoryFactory(
       std::unique_ptr<SharedMemoryFactory> shared_memory_factory) override;
   void Capture(const DesktopRegion& region) override;
   void SetExcludedWindow(WindowId window) override;
 
  private:
   // DesktopCapturer::Callback interface.
-  void OnCaptureCompleted(DesktopFrame* frame) override;
+  void OnCaptureResult(DesktopCapturer::Result result,
+                       std::unique_ptr<DesktopFrame> frame) override;
 
   // MouseCursorMonitor::Callback interface.
   void OnMouseCursor(MouseCursor* cursor) override;
   void OnMouseCursorPosition(MouseCursorMonitor::CursorState state,
                              const DesktopVector& position) override;
 
   std::unique_ptr<DesktopCapturer> desktop_capturer_;
   std::unique_ptr<MouseCursorMonitor> mouse_monitor_;
 
   DesktopCapturer::Callback* callback_;
 
   std::unique_ptr<MouseCursor> cursor_;
   MouseCursorMonitor::CursorState cursor_state_;
   DesktopVector cursor_position_;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(DesktopAndCursorComposer);
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_DESKTOP_AND_CURSOR_COMPOSER_H_