Remove support for old getUserMedia video constraints algorithm.

content/renderer/media/media_stream_video_source.cc

Index: content/renderer/media/media_stream_video_source.cc
diff --git a/content/renderer/media/media_stream_video_source.cc b/content/renderer/media/media_stream_video_source.cc
index a9e158a65123a644649dab61674df3124a3387d3..54852968b1f2fd4b606abe57b1aa12b0596a6922 100644
--- a/content/renderer/media/media_stream_video_source.cc
+++ b/content/renderer/media/media_stream_video_source.cc
@@ -23,299 +23,6 @@
 
 namespace content {
 
-namespace {
-
-const char* const kLegalVideoConstraints[] = {"width",
-                                              "height",
-                                              "aspectRatio",
-                                              "frameRate",
-                                              "facingMode",
-                                              "deviceId",
-                                              "groupId",
-                                              "mediaStreamSource",
-                                              "googNoiseReduction",
-                                              "videoKind"};
-
-// Returns true if |constraint| has mandatory constraints.
-bool HasMandatoryConstraints(const blink::WebMediaConstraints& constraints) {
-  return constraints.Basic().HasMandatory();
-}
-
-// Retrieve the desired max width and height from |constraints|. If not set,
-// the |desired_width| and |desired_height| are set to
-// std::numeric_limits<int>::max();
-// If either max or exact width or height is set as a mandatory constraint,
-// the advanced constraints are not checked.
-void GetDesiredMaxWidthAndHeight(const blink::WebMediaConstraints& constraints,
-                                 int* desired_width, int* desired_height) {
-  *desired_width = std::numeric_limits<int>::max();
-  *desired_height = std::numeric_limits<int>::max();
-
-  const auto& basic_constraints = constraints.Basic();
-
-  if (basic_constraints.width.HasMax() || basic_constraints.height.HasMax() ||
-      basic_constraints.width.HasExact() ||
-      basic_constraints.height.HasExact()) {
-    if (basic_constraints.width.HasMax())
-      *desired_width = basic_constraints.width.Max();
-    if (basic_constraints.height.HasMax())
-      *desired_height = basic_constraints.height.Max();
-    // Exact constraints override max constraints if both are specified.
-    // Specifying both in the same structure is meaningless.
-    if (basic_constraints.width.HasExact())
-      *desired_width = basic_constraints.width.Exact();
-    if (basic_constraints.height.HasExact())
-      *desired_height = basic_constraints.height.Exact();
-    return;
-  }
-
-  for (const auto& constraint_set : constraints.Advanced()) {
-    if (constraint_set.width.HasMax())
-      *desired_width = constraint_set.width.Max();
-    if (constraint_set.height.HasMax())
-      *desired_height = constraint_set.height.Max();
-    if (constraint_set.width.HasExact())
-      *desired_width = constraint_set.width.Exact();
-    if (constraint_set.height.HasExact())
-      *desired_height = constraint_set.height.Exact();
-  }
-}
-
-// Retrieve the desired max and min aspect ratio from |constraints|. If not set,
-// the |min_aspect_ratio| is set to 0 and |max_aspect_ratio| is set to
-// std::numeric_limits<double>::max();
-// If either min or max aspect ratio is set as a mandatory constraint, the
-// optional constraints are not checked.
-void GetDesiredMinAndMaxAspectRatio(
-    const blink::WebMediaConstraints& constraints,
-    double* min_aspect_ratio,
-    double* max_aspect_ratio) {
-  *min_aspect_ratio = 0;
-  *max_aspect_ratio = std::numeric_limits<double>::max();
-
-  if (constraints.Basic().aspect_ratio.HasMin() ||
-      constraints.Basic().aspect_ratio.HasMax()) {
-    if (constraints.Basic().aspect_ratio.HasMin())
-      *min_aspect_ratio = constraints.Basic().aspect_ratio.Min();
-    if (constraints.Basic().aspect_ratio.HasMax())
-      *max_aspect_ratio = constraints.Basic().aspect_ratio.Max();
-    return;
-    // Note - the code will ignore attempts at successive refinement
-    // of the aspect ratio with advanced constraint. This may be wrong.
-  }
-  // Note - the code below will potentially pick min and max from different
-  // constraint sets, some of which might have been ignored.
-  for (const auto& constraint_set : constraints.Advanced()) {
-    if (constraint_set.aspect_ratio.HasMin()) {
-      *min_aspect_ratio = constraint_set.aspect_ratio.Min();
-      break;
-    }
-  }
-  for (const auto& constraint_set : constraints.Advanced()) {
-    // Advanced constraint sets with max aspect ratio 0 are unsatisfiable and
-    // must be ignored.
-    if (constraint_set.aspect_ratio.HasMax() &&
-        constraint_set.aspect_ratio.Max() > 0) {
-      *max_aspect_ratio = constraint_set.aspect_ratio.Max();
-      break;
-    }
-  }
-}
-
-// Returns true if |constraints| are fulfilled. |format| can be changed by a
-// constraint, e.g. the frame rate can be changed by setting maxFrameRate.
-bool UpdateFormatForConstraints(
-    const blink::WebMediaTrackConstraintSet& constraints,
-    media::VideoCaptureFormat* format,
-    std::string* failing_constraint_name) {
-  DCHECK(format != NULL);
-
-  if (!format->IsValid())
-    return false;
-
-  // The width and height are matched based on cropping occuring later:
-  // min width/height has to be >= the size of the frame (no upscale).
-  // max width/height just has to be > 0 (we can crop anything too large).
-  if ((constraints.width.HasMin() &&
-       constraints.width.Min() > format->frame_size.width()) ||
-      (constraints.width.HasMax() && constraints.width.Max() <= 0) ||
-      (constraints.width.HasExact() &&
-       constraints.width.Exact() > format->frame_size.width())) {
-    *failing_constraint_name = constraints.width.GetName();
-  } else if ((constraints.height.HasMin() &&
-              constraints.height.Min() > format->frame_size.height()) ||
-             (constraints.height.HasMax() && constraints.height.Max() <= 0) ||
-             (constraints.height.HasExact() &&
-              constraints.height.Exact() > format->frame_size.height())) {
-    *failing_constraint_name = constraints.height.GetName();
-  } else if (constraints.video_kind.HasExact() &&
-             !constraints.video_kind.Matches(GetVideoKindForFormat(*format))) {
-    *failing_constraint_name = constraints.video_kind.GetName();
-  } else if (!constraints.frame_rate.Matches(format->frame_rate)) {
-    if (constraints.frame_rate.HasMax()) {
-      const double value = constraints.frame_rate.Max();
-      // TODO(hta): Check if handling of max = 0.0 is relevant.
-      // (old handling was to set rate to 1.0 if 0.0 was specified)
-      if (constraints.frame_rate.Matches(value)) {
-        format->frame_rate =
-            (format->frame_rate > value) ? value : format->frame_rate;
-        return true;
-      }
-    }
-    *failing_constraint_name = constraints.frame_rate.GetName();
-  } else {
-    return true;
-  }
-
-  DCHECK(!failing_constraint_name->empty());
-  return false;
-}
-
-// Removes media::VideoCaptureFormats from |formats| that don't meet
-// |constraints|.
-void FilterFormatsByConstraints(
-    const blink::WebMediaTrackConstraintSet& constraints,
-    media::VideoCaptureFormats* formats,
-    std::string* failing_constraint_name) {
-  media::VideoCaptureFormats::iterator format_it = formats->begin();
-  while (format_it != formats->end()) {
-    // Modify |format_it| to fulfill the constraint if possible.
-    // Delete it otherwise.
-    if (!UpdateFormatForConstraints(constraints, &(*format_it),
-                                    failing_constraint_name)) {
-      DVLOG(2) << "Format filter: Discarding format "
-               << format_it->frame_size.width() << "x"
-               << format_it->frame_size.height() << "@"
-               << format_it->frame_rate;
-      format_it = formats->erase(format_it);
-    } else {
-      ++format_it;
-    }
-  }
-}
-
-// Returns the media::VideoCaptureFormats that matches |constraints|.
-// If the return value is empty, and the reason is a specific constraint,
-// |unsatisfied_constraint| returns the name of the constraint.
-media::VideoCaptureFormats FilterFormats(
-    const blink::WebMediaConstraints& constraints,
-    const media::VideoCaptureFormats& supported_formats,
-    std::string* unsatisfied_constraint) {
-  if (constraints.IsNull())
-    return supported_formats;
-
-  const auto& basic = constraints.Basic();
-
-  // Do some checks that won't be done when filtering candidates.
-
-  if (basic.width.HasMin() && basic.width.HasMax() &&
-      basic.width.Min() > basic.width.Max()) {
-    *unsatisfied_constraint = basic.width.GetName();
-    return media::VideoCaptureFormats();
-  }
-
-  if (basic.height.HasMin() && basic.height.HasMax() &&
-      basic.height.Min() > basic.height.Max()) {
-    *unsatisfied_constraint = basic.height.GetName();
-    return media::VideoCaptureFormats();
-  }
-
-  double max_aspect_ratio;
-  double min_aspect_ratio;
-  GetDesiredMinAndMaxAspectRatio(constraints,
-                                 &min_aspect_ratio,
-                                 &max_aspect_ratio);
-
-  if (min_aspect_ratio > max_aspect_ratio || max_aspect_ratio < 0.05f) {
-    DLOG(WARNING) << "Wrong requested aspect ratio: min " << min_aspect_ratio
-                  << " max " << max_aspect_ratio;
-    *unsatisfied_constraint = basic.aspect_ratio.GetName();
-    return media::VideoCaptureFormats();
-  }
-
-  std::vector<std::string> temp(
-      &kLegalVideoConstraints[0],
-      &kLegalVideoConstraints[sizeof(kLegalVideoConstraints) /
-                              sizeof(kLegalVideoConstraints[0])]);
-  std::string failing_name;
-  if (basic.HasMandatoryOutsideSet(temp, failing_name)) {
-    *unsatisfied_constraint = failing_name;
-    return media::VideoCaptureFormats();
-  }
-
-  media::VideoCaptureFormats candidates = supported_formats;
-  FilterFormatsByConstraints(basic, &candidates, unsatisfied_constraint);
-
-  if (candidates.empty())
-    return candidates;
-
-  // Ok - all mandatory checked and we still have candidates.
-  // Let's try filtering using the advanced constraints. The advanced
-  // constraints must be filtered in the order they occur in |advanced|.
-  // But if a constraint produce zero candidates, the constraint is ignored and
-  // the next constraint is tested.
-  // http://w3c.github.io/mediacapture-main/getusermedia.html#dfn-selectsettings
-  for (const auto& constraint_set : constraints.Advanced()) {
-    media::VideoCaptureFormats current_candidates = candidates;
-    std::string unsatisfied_constraint;
-    FilterFormatsByConstraints(constraint_set, &current_candidates,
-                               &unsatisfied_constraint);
-    if (!current_candidates.empty())
-      candidates = current_candidates;
-  }
-
-  // We have done as good as we can to filter the supported resolutions.
-  return candidates;
-}
-
-media::VideoCaptureFormat GetBestFormatBasedOnArea(
-    const media::VideoCaptureFormats& formats,
-    int area) {
-  DCHECK(!formats.empty());
-  const media::VideoCaptureFormat* best_format = nullptr;
-  int best_diff = std::numeric_limits<int>::max();
-  for (const auto& format : formats) {
-    const int diff = abs(area - format.frame_size.GetArea());
-    if (diff < best_diff) {
-      best_diff = diff;
-      best_format = &format;
-    }
-  }
-  DVLOG(3) << "GetBestFormatBasedOnArea chose format "
-           << media::VideoCaptureFormat::ToString(*best_format);
-  return *best_format;
-}
-
-// Find the format that best matches the default video size.
-// This algorithm is chosen since a resolution must be picked even if no
-// constraints are provided. We don't just select the maximum supported
-// resolution since higher resolutions cost more in terms of complexity and
-// many cameras have lower frame rate and have more noise in the image at
-// their maximum supported resolution.
-media::VideoCaptureFormat GetBestCaptureFormat(
-    const media::VideoCaptureFormats& formats,
-    const blink::WebMediaConstraints& constraints) {
-  DCHECK(!formats.empty());
-
-  int max_width;
-  int max_height;
-  GetDesiredMaxWidthAndHeight(constraints, &max_width, &max_height);
-  const int area =
-      std::min(max_width,
-               static_cast<int>(MediaStreamVideoSource::kDefaultWidth)) *
-      std::min(max_height,
-               static_cast<int>(MediaStreamVideoSource::kDefaultHeight));
-
-  return GetBestFormatBasedOnArea(formats, area);
-}
-
-}  // anonymous namespace
-
-bool IsOldVideoConstraints() {
-  return base::FeatureList::IsEnabled(
-      features::kMediaStreamOldVideoConstraints);
-}
-
 // static
 MediaStreamVideoSource* MediaStreamVideoSource::GetVideoSource(
     const blink::WebMediaStreamSource& source) {
@@ -336,62 +43,6 @@ MediaStreamVideoSource::~MediaStreamVideoSource() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 }
 
-void MediaStreamVideoSource::AddTrackLegacy(
-    MediaStreamVideoTrack* track,
-    const VideoCaptureDeliverFrameCB& frame_callback,
-    const blink::WebMediaConstraints& constraints,
-    const ConstraintsCallback& callback) {
-  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  DCHECK(IsOldVideoConstraints());
-  DCHECK(!constraints.IsNull());
-  DCHECK(std::find(tracks_.begin(), tracks_.end(), track) == tracks_.end());
-  tracks_.push_back(track);
-  secure_tracker_.Add(track, true);
-
-  track_descriptors_.push_back(
-      TrackDescriptor(track, frame_callback, constraints, callback));
-
-  switch (state_) {
-    case NEW: {
-      // Tab capture and Screen capture needs the maximum requested height
-      // and width to decide on the resolution.
-      // NOTE: Optional constraints are deliberately ignored.
-      int max_requested_width = 0;
-      if (constraints.Basic().width.HasMax())
-        max_requested_width = constraints.Basic().width.Max();
-
-      int max_requested_height = 0;
-      if (constraints.Basic().height.HasMax())
-        max_requested_height = constraints.Basic().height.Max();
-
-      double max_requested_frame_rate = kDefaultFrameRate;
-      if (constraints.Basic().frame_rate.HasMax())
-        max_requested_frame_rate = constraints.Basic().frame_rate.Max();
-
-      state_ = RETRIEVING_CAPABILITIES;
-      GetCurrentSupportedFormats(
-          max_requested_width,
-          max_requested_height,
-          max_requested_frame_rate,
-          base::Bind(&MediaStreamVideoSource::OnSupportedFormats,
-                     weak_factory_.GetWeakPtr()));
-
-      break;
-    }
-    case STARTING:
-    case RETRIEVING_CAPABILITIES: {
-      // The |callback| will be triggered once the source has started or
-      // the capabilities have been retrieved.
-      break;
-    }
-    case ENDED:
-    case STARTED: {
-      // Currently, reconfiguring the source is not supported.
-      FinalizeAddTrackLegacy();
-    }
-  }
-}
-
 void MediaStreamVideoSource::AddTrack(
     MediaStreamVideoTrack* track,
     const VideoTrackAdapterSettings& track_adapter_settings,
@@ -419,10 +70,6 @@ void MediaStreamVideoSource::AddTrack(
     case STARTING: {
       break;
     }
-    case RETRIEVING_CAPABILITIES: {
-      NOTREACHED();
-      break;
-    }
     case ENDED:
     case STARTED: {
       // Currently, reconfiguring the source is not supported.
@@ -485,13 +132,7 @@ base::SingleThreadTaskRunner* MediaStreamVideoSource::io_task_runner() const {
 base::Optional<media::VideoCaptureFormat>
 MediaStreamVideoSource::GetCurrentFormat() const {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  if (IsOldVideoConstraints()) {
-    if (state_ == STARTING || state_ == STARTED)
-      return current_format_;
-    return base::Optional<media::VideoCaptureFormat>();
-  } else {
-    return GetCurrentFormatImpl();
-  }
+  return GetCurrentFormatImpl();
 }
 
 base::Optional<media::VideoCaptureFormat>
@@ -510,76 +151,6 @@ void MediaStreamVideoSource::DoStopSource() {
   SetReadyState(blink::WebMediaStreamSource::kReadyStateEnded);
 }
 
-void MediaStreamVideoSource::OnSupportedFormats(
-    const media::VideoCaptureFormats& formats) {
-  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  DCHECK(IsOldVideoConstraints());
-  DCHECK_EQ(RETRIEVING_CAPABILITIES, state_);
-
-  supported_formats_ = formats;
-  blink::WebMediaConstraints fulfilled_constraints;
-  if (!FindBestFormatWithConstraints(supported_formats_,
-                                     &current_format_,
-                                     &fulfilled_constraints)) {
-    SetReadyState(blink::WebMediaStreamSource::kReadyStateEnded);
-    DVLOG(3) << "OnSupportedFormats failed to find an usable format";
-    // This object can be deleted after calling FinalizeAddTrack. See comment
-    // in the header file.
-    FinalizeAddTrackLegacy();
-    return;
-  }
-
-  state_ = STARTING;
-  DVLOG(3) << "Starting the capturer with "
-           << media::VideoCaptureFormat::ToString(current_format_);
-
-  StartSourceImpl(
-      current_format_,
-      fulfilled_constraints,
-      base::Bind(&VideoTrackAdapter::DeliverFrameOnIO, track_adapter_));
-}
-
-bool MediaStreamVideoSource::FindBestFormatWithConstraints(
-    const media::VideoCaptureFormats& formats,
-    media::VideoCaptureFormat* best_format,
-    blink::WebMediaConstraints* fulfilled_constraints) {
-  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  DVLOG(3) << "MediaStreamVideoSource::FindBestFormatWithConstraints "
-           << "with " << formats.size() << " formats";
-  // Find the first track descriptor that can fulfil the constraints.
-  for (const auto& track : track_descriptors_) {
-    const blink::WebMediaConstraints& track_constraints = track.constraints;
-
-    // If the source doesn't support capability enumeration it is still ok if
-    // no mandatory constraints have been specified. That just means that
-    // we will start with whatever format is native to the source.
-    if (formats.empty() && !HasMandatoryConstraints(track_constraints)) {
-      DVLOG(3) << "No mandatory constraints and no formats";
-      *fulfilled_constraints = track_constraints;
-      *best_format = media::VideoCaptureFormat();
-      return true;
-    }
-    std::string unsatisfied_constraint;
-    const media::VideoCaptureFormats filtered_formats =
-        FilterFormats(track_constraints, formats, &unsatisfied_constraint);
-    if (filtered_formats.empty())
-      continue;
-
-    // A request with constraints that can be fulfilled.
-    *fulfilled_constraints = track_constraints;
-    media::VideoCaptureFormat best_format_candidate =
-        GetBestCaptureFormat(filtered_formats, track_constraints);
-    if (!best_format_candidate.IsValid())
-      continue;
-
-    *best_format = best_format_candidate;
-    DVLOG(3) << "Found a track that matches the constraints";
-    return true;
-  }
-  DVLOG(3) << "No usable format found";
-  return false;
-}
-
 void MediaStreamVideoSource::OnStartDone(MediaStreamRequestResult result) {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   DVLOG(3) << "OnStartDone({result =" << result << "})";
@@ -598,76 +169,11 @@ void MediaStreamVideoSource::OnStartDone(MediaStreamRequestResult result) {
 
   // This object can be deleted after calling FinalizeAddTrack. See comment in
   // the header file.
-  if (IsOldVideoConstraints())
-    FinalizeAddTrackLegacy();
-  else
-    FinalizeAddTrack();
-}
-
-void MediaStreamVideoSource::FinalizeAddTrackLegacy() {
-  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  DCHECK(IsOldVideoConstraints());
-  const media::VideoCaptureFormats formats(1, current_format_);
-
-  std::vector<TrackDescriptor> track_descriptors;
-  track_descriptors.swap(track_descriptors_);
-  for (const auto& track : track_descriptors) {
-    MediaStreamRequestResult result = MEDIA_DEVICE_OK;
-    std::string unsatisfied_constraint;
-
-    if (HasMandatoryConstraints(track.constraints) &&
-        FilterFormats(track.constraints, formats, &unsatisfied_constraint)
-            .empty()) {
-      result = MEDIA_DEVICE_CONSTRAINT_NOT_SATISFIED;
-      DVLOG(3) << "FinalizeAddTrackLegacy() ignoring device on constraint "
-               << unsatisfied_constraint;
-    }
-
-    if (state_ != STARTED && result == MEDIA_DEVICE_OK)
-      result = MEDIA_DEVICE_TRACK_START_FAILURE;
-
-    if (result == MEDIA_DEVICE_OK) {
-      int max_width;
-      int max_height;
-      GetDesiredMaxWidthAndHeight(track.constraints, &max_width, &max_height);
-      double max_aspect_ratio;
-      double min_aspect_ratio;
-      GetDesiredMinAndMaxAspectRatio(track.constraints,
-                                     &min_aspect_ratio,
-                                     &max_aspect_ratio);
-      double max_frame_rate = 0.0f;
-      // Note: Optional and ideal constraints are ignored; this is
-      // purely a hard max limit.
-      if (track.constraints.Basic().frame_rate.HasMax())
-        max_frame_rate = track.constraints.Basic().frame_rate.Max();
-
-      track_adapter_->AddTrack(
-          track.track, track.frame_callback,
-          VideoTrackAdapterSettings(max_width, max_height, min_aspect_ratio,
-                                    max_aspect_ratio, max_frame_rate,
-                                    base::Optional<gfx::Size>()));
-      // Calculate resulting frame size if the source delivers frames
-      // according to the current format. Note: Format may change later.
-      gfx::Size desired_size;
-      VideoTrackAdapter::CalculateTargetSize(
-          false /* is_rotated */, current_format_.frame_size,
-          gfx::Size(max_width, max_height), min_aspect_ratio, max_aspect_ratio,
-          &desired_size);
-      track.track->SetTargetSizeAndFrameRate(
-          desired_size.width(), desired_size.height(), max_frame_rate);
-    }
-
-    DVLOG(3) << "FinalizeAddTrackLegacy() result " << result;
-
-    if (!track.callback.is_null())
-      track.callback.Run(this, result,
-                         blink::WebString::FromUTF8(unsatisfied_constraint));
-  }
+  FinalizeAddTrack();
 }
 
 void MediaStreamVideoSource::FinalizeAddTrack() {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
-  DCHECK(!IsOldVideoConstraints());
   std::vector<TrackDescriptor> track_descriptors;
   track_descriptors.swap(track_descriptors_);
   for (const auto& track : track_descriptors) {
@@ -721,18 +227,6 @@ void MediaStreamVideoSource::SetMutedState(bool muted_state) {
   }
 }
 
-MediaStreamVideoSource::TrackDescriptor::TrackDescriptor(
-    MediaStreamVideoTrack* track,
-    const VideoCaptureDeliverFrameCB& frame_callback,
-    const blink::WebMediaConstraints& constraints,
-    const ConstraintsCallback& callback)
-    : track(track),
-      frame_callback(frame_callback),
-      constraints(constraints),
-      callback(callback) {
-  DCHECK(IsOldVideoConstraints());
-}
-
 MediaStreamVideoSource::TrackDescriptor::TrackDescriptor(
     MediaStreamVideoTrack* track,
     const VideoCaptureDeliverFrameCB& frame_callback,
@@ -741,9 +235,7 @@ MediaStreamVideoSource::TrackDescriptor::TrackDescriptor(
     : track(track),
       frame_callback(frame_callback),
       adapter_settings(std::move(adapter_settings)),
-      callback(callback) {
-  DCHECK(!IsOldVideoConstraints());
-}
+      callback(callback) {}
 
 MediaStreamVideoSource::TrackDescriptor::TrackDescriptor(
     TrackDescriptor&& other) = default;