DirectX capturer flickers on the second monitor

webrtc/modules/desktop_capture/win/dxgi_output_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 145 matching lines @@
     if (!texture_->CopyFrom(frame_info, resource.Get(),
                             context->updated_region)) {
       return false;
     }
     SpreadContextChange(context);
     updated_region.AddRegion(context->updated_region);
 
     const DesktopFrame& source = texture_->AsDesktopFrame();
     for (DesktopRegion::Iterator it(updated_region); !it.IsAtEnd();
          it.Advance()) {
-      target->CopyPixelsFrom(source, SourceRect(it.rect()).top_left(),
-                             TargetRect(it.rect(), offset));
+      target->CopyPixelsFrom(
+          source, SourceRect(it.rect()).top_left(), it.rect());
     }
     last_frame_ = target->Share();
     last_frame_offset_ = offset;
     target->mutable_updated_region()->AddRegion(updated_region);
     return texture_->Release() && ReleaseFrame();
   }
 
   if (last_frame_) {
     // No change since last frame or AcquireNextFrame() timed out, we will
     // export last frame to the target.
     for (DesktopRegion::Iterator it(updated_region); !it.IsAtEnd();
          it.Advance()) {
-      target->CopyPixelsFrom(*last_frame_, SourceRect(it.rect()).top_left(),
-                             TargetRect(it.rect(), offset));
+      target->CopyPixelsFrom(*last_frame_, it.rect().top_left(), it.rect());
     }
     target->mutable_updated_region()->AddRegion(updated_region);
   }
   // If AcquireNextFrame() failed with timeout error, we do not need to release
   // the frame.
   return error.Error() == DXGI_ERROR_WAIT_TIMEOUT || ReleaseFrame();
 }
 
 DesktopRect DxgiOutputDuplicator::TranslatedDesktopRect(DesktopVector offset) {
   DesktopRect result(DesktopRect::MakeSize(desktop_rect_.size()));
@@ skipping 103 matching lines @@
     }
   }
 }
 
 DesktopRect DxgiOutputDuplicator::SourceRect(DesktopRect rect) {
   // |texture_|->AsDesktopFrame() starts from (0, 0).
   rect.Translate(-desktop_rect_.left(), -desktop_rect_.top());
   return rect;
 }
 
-DesktopRect DxgiOutputDuplicator::TargetRect(DesktopRect rect,
-                                             DesktopVector offset) {
-  rect = SourceRect(rect);
-  rect.Translate(offset);
-  return rect;
-}
-
 }  // namespace webrtc