Output DeviceName from various windows ScreenCapturer related implementations

webrtc/modules/desktop_capture/win/screen_capture_utils.cc

 /*
  *  Copyright (c) 2014 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/win/screen_capture_utils.h"
 
 #include <windows.h>
 
 #include "webrtc/rtc_base/checks.h"
+#include "webrtc/rtc_base/win32.h"
 
 namespace webrtc {
 
-bool GetScreenList(DesktopCapturer::SourceList* screens) {
-  RTC_DCHECK(screens->size() == 0);
+bool GetScreenList(DesktopCapturer::SourceList* screens,
+                   std::vector<std::string>* device_names /* = nullptr */) {
+  RTC_DCHECK_EQ(screens->size(), 0U);
+  if (device_names) {
+    RTC_DCHECK_EQ(device_names->size(), 0U);
+  }
 
   BOOL enum_result = TRUE;
   for (int device_index = 0;; ++device_index) {
     DISPLAY_DEVICE device;
     device.cb = sizeof(device);
     enum_result = EnumDisplayDevices(NULL, device_index, &device, 0);
 
     // |enum_result| is 0 if we have enumerated all devices.
     if (!enum_result)
       break;
 
     // We only care about active displays.
     if (!(device.StateFlags & DISPLAY_DEVICE_ACTIVE))
       continue;
 
     screens->push_back({device_index, std::string()});
+    if (device_names) {
+      device_names->push_back(rtc::ToUtf8(device.DeviceName));
+    }
   }
   return true;
 }
 
 bool IsScreenValid(DesktopCapturer::SourceId screen, std::wstring* device_key) {
   if (screen == kFullDesktopScreenId) {
     *device_key = L"";
     return true;
   }
 
@@ skipping 36 matching lines @@
   if (!result)
     return DesktopRect();
 
   return DesktopRect::MakeXYWH(device_mode.dmPosition.x,
                                device_mode.dmPosition.y,
                                device_mode.dmPelsWidth,
                                device_mode.dmPelsHeight);
 }
 
 }  // namespace webrtc