Revert of BlankDetectorDesktopCapturerWrapper to detect a blank DesktopFrame

webrtc/modules/desktop_capture/rgba_color.h

 /*
  *  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.
  */
 
 #ifndef WEBRTC_MODULES_DESKTOP_CAPTURE_RGBA_COLOR_H_
 #define WEBRTC_MODULES_DESKTOP_CAPTURE_RGBA_COLOR_H_
 
 #include <stdint.h>
 
 #include "webrtc/modules/desktop_capture/desktop_frame.h"
 
 namespace webrtc {
 
 // A four-byte structure to store a color in BGRA format. This structure also
 // provides functions to be created from uint8_t array, say,
 // DesktopFrame::data(). It always uses BGRA order for internal storage to match
 // DesktopFrame::data().
+//
+// This struct is for testing purpose only, and should not be used in production
+// logic.
 struct RgbaColor final {
   // Creates a color with BGRA channels.
   RgbaColor(uint8_t blue, uint8_t green, uint8_t red, uint8_t alpha);
 
   // Creates a color with BGR channels, and set alpha channel to 255 (opaque).
   RgbaColor(uint8_t blue, uint8_t green, uint8_t red);
 
   // Creates a color from four-byte in BGRA order, i.e. DesktopFrame::data().
   explicit RgbaColor(const uint8_t* bgra);
 
@@ skipping 16 matching lines @@
   uint8_t red;
   uint8_t alpha;
 };
 static_assert(
     DesktopFrame::kBytesPerPixel == sizeof(RgbaColor),
     "A pixel in DesktopFrame should be safe to be represented by a RgbaColor");
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_RGBA_COLOR_H_