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

webrtc/modules/desktop_capture/win/dxgi_adapter_duplicator.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 58 matching lines @@
         if (error.Error() != S_OK || !output1) {
           LOG(LS_WARNING) << "Failed to convert IDXGIOutput to IDXGIOutput1, "
                              "this usually means the system does not support "
                              "DirectX 11";
           return false;
         }
         duplicators_.emplace_back(device_, output1, desc);
         if (!duplicators_.back().Initialize()) {
           return false;
         }
-        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());
       }
     } else {
       LOG(LS_WARNING) << "Failed to get output description of device " << i
                       << ", ignore.";
     }
   }
   return true;
 }
 
 void DxgiAdapterDuplicator::Setup(Context* context) {
@@ skipping 54 matching lines @@
 
 void DxgiAdapterDuplicator::TranslateRect(const DesktopVector& position) {
   desktop_rect_.Translate(position);
   RTC_DCHECK(desktop_rect_.left() >= 0 && desktop_rect_.top() >= 0);
   for (auto& duplicator : duplicators_) {
     duplicator.TranslateRect(position);
   }
 }
 
 }  // namespace webrtc