Merge ScreenCapturerWinDirectx::frames_ and contexts_

webrtc/modules/desktop_capture/win/dxgi_context.h

+/*
+ *  Copyright (c) 2017 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.
+ */
+
+#ifndef WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_DXGI_CONTEXT_H_
+#define WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_DXGI_CONTEXT_H_
+
+#include <vector>
+#include "webrtc/modules/desktop_capture/desktop_region.h"
+
+namespace webrtc {
+
+struct OutputContext final {
+  // The updated region DxgiOutputDuplicator::DetectUpdatedRegion() output
+  // during last Duplicate() function call. It's always relative to the (0, 0).
+  DesktopRegion updated_region;
+};
+
+// An AdapterContext stores the status of a single DxgiFrame of
+// DxgiAdapterDuplicator.
+struct AdapterContext final {
+  AdapterContext();
+  AdapterContext(const AdapterContext& other);
+  ~AdapterContext();
+
+  // Child OutputContext belongs to this AdapterContext.
+  std::vector<OutputContext> contexts;
+};
+
+// A Context stores the status of a single DxgiFrame of
+// DxgiDuplicatorController.
+struct Context final {

[Sergey Ulanov, 2017/04/19 23:29:28]

Thank you for moving these structs to this file. I think it does make it easier
to understand how they are related to each other. 
I think the names are too generic to put them in webrtc namespace. I suggest
renaming them as DxgiOutputContext, DxgiAdapterContext and DxgiFrameContext

[Hzj_jie, 2017/04/20 01:07:28]

Done.
Indeed I think we have too many DXGI components, which deserve a standalone
namespace.

+ public:
+  Context();
+  // Unregister this Context instance from DxgiDuplicatorController during
+  // destructing.
+  ~Context();
+
+  // Reset current Context, so it will be reinitialized next time.
+  void Reset();
+
+  // A Context will have an exactly same |controller_id| as
+  // DxgiDuplicatorController, to ensure it has been correctly setted up after
+  // each DxgiDuplicatorController::Initialize().
+  int controller_id = 0;
+
+  // Child AdapterContext belongs to this Context.
+  std::vector<AdapterContext> contexts;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_DXGI_CONTEXT_H_