[WebRTC] Two DirectX capturers cannot work concurrently

webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.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.
  */
 
@@ skipping 95 matching lines @@
 }
 
 void DxgiAdapterDuplicator::Unregister(const Context* const context) {
   RTC_DCHECK_EQ(context->contexts.size(), duplicators_.size());
   for (size_t i = 0; i < duplicators_.size(); i++) {
     duplicators_[i].Unregister(&context->contexts[i]);
   }
 }
 
 bool DxgiAdapterDuplicator::Duplicate(Context* context,
-                                      const DesktopFrame* last_frame,
-                                      DesktopFrame* target) {
+                                      SharedDesktopFrame* target) {
   RTC_DCHECK_EQ(context->contexts.size(), duplicators_.size());
   for (size_t i = 0; i < duplicators_.size(); i++) {
-    if (!duplicators_[i].Duplicate(&context->contexts[i], last_frame,
+    if (!duplicators_[i].Duplicate(&context->contexts[i],
                                    duplicators_[i].desktop_rect().top_left(),
                                    target)) {
       return false;
     }
   }
   return true;
 }
 
 bool DxgiAdapterDuplicator::DuplicateMonitor(Context* context,
                                              int monitor_id,
-                                             const DesktopFrame* last_frame,
-                                             DesktopFrame* target) {
+                                             SharedDesktopFrame* target) {
   RTC_DCHECK(monitor_id >= 0 &&
              monitor_id < static_cast<int>(duplicators_.size()) &&
              context->contexts.size() == duplicators_.size());
-  return duplicators_[monitor_id].Duplicate(
-      &context->contexts[monitor_id], last_frame, DesktopVector(), target);
+  return duplicators_[monitor_id].Duplicate(&context->contexts[monitor_id],
+                                            DesktopVector(), target);
 }
 
 DesktopRect DxgiAdapterDuplicator::ScreenRect(int id) const {
   RTC_DCHECK(id >= 0 && id < static_cast<int>(duplicators_.size()));
   return duplicators_[id].desktop_rect();
 }
 
 }  // namespace webrtc