Revert of Add DesktopCapturer GetSourceList SelectSource FocusOnSelectedSource functions

webrtc/modules/desktop_capture/desktop_capturer.cc

-/*
- *  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.
- */
-
-#include "webrtc/modules/desktop_capture/desktop_capturer.h"
-
-#include "webrtc/modules/desktop_capture/desktop_capture_options.h"
-#include "webrtc/modules/desktop_capture/screen_capturer_differ_wrapper.h"
-
-namespace webrtc {
-
-DesktopCapturer::~DesktopCapturer() = default;
-
-void DesktopCapturer::SetSharedMemoryFactory(
-    std::unique_ptr<SharedMemoryFactory> shared_memory_factory) {}
-
-void DesktopCapturer::SetExcludedWindow(WindowId window) {}
-
-bool DesktopCapturer::GetSourceList(SourceList* sources) {
-  return true;
-}
-
-bool DesktopCapturer::SelectSource(SourceId id) {
-  return false;
-}
-
-bool DesktopCapturer::FocusOnSelectedSource() {
-  return false;
-}
-
-}  // namespace webrtc