Skips the first frame in DxgiDuplicatorController

webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.cc

Index: webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.cc
diff --git a/webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.cc b/webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.cc
index 443770f1eefdb07afdf98bbb4a30ce12ba936d2d..52bf2a194b0aae33190689b53c6cdd76290d25f5 100644
--- a/webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.cc
+++ b/webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.cc
@@ -144,4 +144,17 @@ DesktopRect DxgiAdapterDuplicator::ScreenRect(int id) const {
   return duplicators_[id].desktop_rect();
 }
 
+int DxgiAdapterDuplicator::screen_count() const {
+  return static_cast<int>(duplicators_.size());
+}
+
+int64_t DxgiAdapterDuplicator::GetNumFramesCaptured() const {
+  int64_t min = INT64_MAX;
+  for (const auto& duplicator : duplicators_) {
+    min = std::min(min, duplicator.num_frames_captured());
+  }
+
+  return min;
+}
+
 }  // namespace webrtc