Introduce SelectSettings algorithm for MediaStream video tracks.

content/renderer/media/media_stream_constraints_util_video_content.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_MEDIA_MEDIA_STREAM_CONSTRAINTS_UTIL_VIDEO_CONTENT_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_CONSTRAINTS_UTIL_VIDEO_CONTENT_H_
 
 #include <string>
 
-#include "base/logging.h"
 #include "content/common/content_export.h"
-#include "media/capture/video_capture_types.h"
+#include "content/renderer/media/media_stream_constraints_util.h"
 #include "third_party/webrtc/base/optional.h"
 
 namespace blink {
 class WebMediaConstraints;
 }
 
 namespace content {
 
-class CONTENT_EXPORT VideoContentCaptureSourceSelectionResult {
- public:
-  // Creates a result without value and with an empty failed constraint name.
-  VideoContentCaptureSourceSelectionResult();
+CONTENT_EXPORT extern const int kDefaultScreenCastWidth;
+CONTENT_EXPORT extern const int kDefaultScreenCastHeight;
+CONTENT_EXPORT extern const double kDefaultScreenCastFrameRate;
+CONTENT_EXPORT extern const int kMinScreenCastDimension;
+CONTENT_EXPORT extern const int kMaxScreenCastDimension;
 
-  // Creates a result without value and with the given |failed_constraint_name|.
-  // Does not take ownership of |failed_constraint_name|, so it must be null or
-  // point to a string that remains accessible.
-  explicit VideoContentCaptureSourceSelectionResult(
-      const char* failed_constraint_name);
-
-  // Creates a result with the given values.
-  VideoContentCaptureSourceSelectionResult(
-      std::string device_id,
-      const rtc::Optional<bool>& noise_reduction,
-      media::VideoCaptureParams capture_params);
-
-  VideoContentCaptureSourceSelectionResult(
-      const VideoContentCaptureSourceSelectionResult& other);
-  VideoContentCaptureSourceSelectionResult& operator=(
-      const VideoContentCaptureSourceSelectionResult& other);
-  VideoContentCaptureSourceSelectionResult(
-      VideoContentCaptureSourceSelectionResult&& other);
-  VideoContentCaptureSourceSelectionResult& operator=(
-      VideoContentCaptureSourceSelectionResult&& other);
-  ~VideoContentCaptureSourceSelectionResult();
-
-  bool HasValue() const { return failed_constraint_name_ == nullptr; }
-
-  // Accessors.
-  const char* failed_constraint_name() const { return failed_constraint_name_; }
-  const std::string& device_id() const {
-    DCHECK(HasValue());
-    return device_id_;
-  }
-  const rtc::Optional<bool>& noise_reduction() const {
-    DCHECK(HasValue());
-    return noise_reduction_;
-  }
-  media::VideoCaptureParams capture_params() const {
-    DCHECK(HasValue());
-    return capture_params_;
-  }
-
-  // Convenience accessors for fields embedded in the |capture_params_| field.
-  int Height() const;
-  int Width() const;
-  float FrameRate() const;
-  media::ResolutionChangePolicy ResolutionChangePolicy() const;
-
- private:
-  const char* failed_constraint_name_;
-  std::string device_id_;
-  rtc::Optional<bool> noise_reduction_;
-  media::VideoCaptureParams capture_params_;
-};
-
-// This function performs source and source-settings selection for content
-// video capture based on the given |constraints|.
-VideoContentCaptureSourceSelectionResult CONTENT_EXPORT
-SelectVideoContentCaptureSourceSettings(
+// This function performs source, source-settings and track-settings selection
+// for content video capture based on the given |constraints|.
+VideoCaptureSettings CONTENT_EXPORT SelectSettingsVideoContentCapture(
     const blink::WebMediaConstraints& constraints);
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_CONSTRAINTS_UTIL_VIDEO_CONTENT_H_