Add reference counter of DxgiDuplicatorController to unload DXGI components

webrtc/modules/desktop_capture/win/screen_capturer_win_directx.cc

Index: webrtc/modules/desktop_capture/win/screen_capturer_win_directx.cc
diff --git a/webrtc/modules/desktop_capture/win/screen_capturer_win_directx.cc b/webrtc/modules/desktop_capture/win/screen_capturer_win_directx.cc
index 9630265c63e8720ee3089b9fccb9f1b873aa05e8..331379b8a56d0e7307c500a810ac8336bdddb068 100644
--- a/webrtc/modules/desktop_capture/win/screen_capturer_win_directx.cc
+++ b/webrtc/modules/desktop_capture/win/screen_capturer_win_directx.cc
@@ -36,11 +36,10 @@ bool ScreenCapturerWinDirectx::RetrieveD3dInfo(D3dInfo* info) {
   return DxgiDuplicatorController::Instance()->RetrieveD3dInfo(info);
 }
 
-ScreenCapturerWinDirectx::ScreenCapturerWinDirectx(
-    const DesktopCaptureOptions& options)
-    : callback_(nullptr) {}
+ScreenCapturerWinDirectx::ScreenCapturerWinDirectx()
+    : controller_(DxgiDuplicatorController::Instance()) {}
 
-ScreenCapturerWinDirectx::~ScreenCapturerWinDirectx() {}
+ScreenCapturerWinDirectx::~ScreenCapturerWinDirectx() = default;
 
 void ScreenCapturerWinDirectx::Start(Callback* callback) {
   RTC_DCHECK(!callback_);
@@ -67,10 +66,9 @@ void ScreenCapturerWinDirectx::CaptureFrame() {
 
   DxgiDuplicatorController::Result result;
   if (current_screen_id_ == kFullDesktopScreenId) {
-    result = DxgiDuplicatorController::Instance()->Duplicate(
-        frames_.current_frame());
+    result = controller_->Duplicate(frames_.current_frame());
   } else {
-    result = DxgiDuplicatorController::Instance()->DuplicateMonitor(
+    result = controller_->DuplicateMonitor(
         frames_.current_frame(), current_screen_id_);
   }
 
@@ -106,7 +104,7 @@ void ScreenCapturerWinDirectx::CaptureFrame() {
 }
 
 bool ScreenCapturerWinDirectx::GetSourceList(SourceList* sources) {
-  int screen_count = DxgiDuplicatorController::Instance()->ScreenCount();
+  int screen_count = controller_->ScreenCount();
   for (int i = 0; i < screen_count; i++) {
     sources->push_back({i});
   }
@@ -123,7 +121,7 @@ bool ScreenCapturerWinDirectx::SelectSource(SourceId id) {
     return true;
   }
 
-  int screen_count = DxgiDuplicatorController::Instance()->ScreenCount();
+  int screen_count = controller_->ScreenCount();
   if (id >= 0 && id < screen_count) {
     current_screen_id_ = id;
     return true;