[Chromoting] Improve DirectX capturer to support multiple outputs

webrtc/modules/desktop_capture/win/dxgi_texture.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.
+ */
+
+#include "webrtc/modules/desktop_capture/win/dxgi_texture.h"
+
+namespace webrtc {
+
+DxgiTexture::DxgiTexture(const DesktopRect& desktop_rect)
+    : desktop_rect_(desktop_rect) {}
+
+DxgiTexture::DxgiDesktopFrame::DxgiDesktopFrame(const DxgiTexture& texture)
+    : DesktopFrame(texture.desktop_rect().size(),
+                   texture.pitch(),
+                   texture.bits(),
+                   nullptr) {}
+
+std::unique_ptr<DesktopFrame> DxgiTexture::AsDesktopFrame() const {
+  return std::unique_ptr<DesktopFrame>(new DxgiDesktopFrame(*this));
+}
+
+}  // namespace webrtc