Cleanup shared memory handling in DesktopCapturer interface.

webrtc/modules/desktop_capture/window_capturer_unittest.cc

 /*
  *  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 12 matching lines @@
                            public DesktopCapturer::Callback {
  public:
   void SetUp() override {
     capturer_.reset(
         WindowCapturer::Create(DesktopCaptureOptions::CreateDefault()));
   }
 
   void TearDown() override {}
 
   // DesktopCapturer::Callback interface
-  SharedMemory* CreateSharedMemory(size_t size) override { return NULL; }
-
   void OnCaptureCompleted(DesktopFrame* frame) override { frame_.reset(frame); }
 
  protected:
   rtc::scoped_ptr<WindowCapturer> capturer_;
   rtc::scoped_ptr<DesktopFrame> frame_;
 };
 
 // Verify that we can enumerate windows.
 TEST_F(WindowCapturerTest, Enumerate) {
   WindowCapturer::WindowList windows;
@@ skipping 36 matching lines @@
       }
       continue;
     }
 
     EXPECT_GT(frame_->size().width(), 0);
     EXPECT_GT(frame_->size().height(), 0);
   }
 }
 
 }  // namespace webrtc