Forward capturer_id to shared desktopframe

webrtc/modules/desktop_capture/shared_desktop_frame.cc

Index: webrtc/modules/desktop_capture/shared_desktop_frame.cc
diff --git a/webrtc/modules/desktop_capture/shared_desktop_frame.cc b/webrtc/modules/desktop_capture/shared_desktop_frame.cc
index fd67c7422920cd2a987108a269fe7e80c5458e5e..d825140828159f2acb6ec62268f434be3b9a290b 100644
--- a/webrtc/modules/desktop_capture/shared_desktop_frame.cc
+++ b/webrtc/modules/desktop_capture/shared_desktop_frame.cc
@@ -37,6 +37,7 @@ std::unique_ptr<SharedDesktopFrame> SharedDesktopFrame::Share() {
   std::unique_ptr<SharedDesktopFrame> result(new SharedDesktopFrame(core_));
   result->set_dpi(dpi());
   result->set_capture_time_ms(capture_time_ms());
+  result->set_capturer_id(capturer_id());
   *result->mutable_updated_region() = updated_region();
   return result;
 }