DesktopRect::UnionWith() to extend current rect to cover the input rect

webrtc/modules/desktop_capture/win/dxgi_duplicator_controller.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 164 matching lines @@
         devices[i].d3d_device()->GetFeatureLevel();
     if (d3d_info_.max_feature_level == 0 ||
         feature_level > d3d_info_.max_feature_level) {
       d3d_info_.max_feature_level = feature_level;
     }
     if (d3d_info_.min_feature_level == 0 ||
         feature_level < d3d_info_.min_feature_level) {
       d3d_info_.min_feature_level = feature_level;
     }
 
-    if (desktop_rect_.is_empty()) {
-      desktop_rect_ = duplicators_.back().desktop_rect();
-    } else {
-      const DesktopRect& left = desktop_rect_;
-      const DesktopRect& right = duplicators_.back().desktop_rect();
-      desktop_rect_ =
-          DesktopRect::MakeLTRB(std::min(left.left(), right.left()),
-                                std::min(left.top(), right.top()),
-                                std::max(left.right(), right.right()),
-                                std::max(left.bottom(), right.bottom()));
-    }
+    desktop_rect_.UnionWith(duplicators_.back().desktop_rect());
   }
   TranslateRect();
 
   HDC hdc = GetDC(nullptr);
   // Use old DPI value if failed.
   if (hdc) {
     dpi_.set(GetDeviceCaps(hdc, LOGPIXELSX), GetDeviceCaps(hdc, LOGPIXELSY));
     ReleaseDC(nullptr, hdc);
   }
 
@@ skipping 176 matching lines @@
 void DxgiDuplicatorController::TranslateRect() {
   const DesktopVector position =
       DesktopVector().subtract(desktop_rect_.top_left());
   desktop_rect_.Translate(position);
   for (auto& duplicator : duplicators_) {
     duplicator.TranslateRect(position);
   }
 }
 
 }  // namespace webrtc