Implement ConstraintNotSatisfiedError for getusermedia

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 42c5b1b4c558aeb7bfcd849c274e95f79d7960a5..8b0d21f6ee2f2a621d313f72e5e18d6fa975ef92 100644
--- a/content/renderer/media/media_stream_video_source.cc
+++ b/content/renderer/media/media_stream_video_source.cc
@@ -220,7 +220,8 @@ void FilterFormatsByConstraint(
 // Returns the media::VideoCaptureFormats that matches |constraints|.
 media::VideoCaptureFormats FilterFormats(
     const blink::WebMediaConstraints& constraints,
-    const media::VideoCaptureFormats& supported_formats) {
+    const media::VideoCaptureFormats& supported_formats,
+    blink::WebString* unsatisfied_constraint) {
   if (constraints.isNull()) {
     return supported_formats;
   }
@@ -270,11 +271,13 @@ media::VideoCaptureFormats FilterFormats(
   constraints.getMandatoryConstraints(mandatory);
   constraints.getOptionalConstraints(optional);
   media::VideoCaptureFormats candidates = supported_formats;
-  for (size_t i = 0; i < mandatory.size(); ++i)
+  for (size_t i = 0; i < mandatory.size(); ++i) {
     FilterFormatsByConstraint(mandatory[i], true, &candidates);
-
-  if (candidates.empty())
-    return candidates;
+    if (candidates.empty()) {
+      *unsatisfied_constraint = mandatory[i].m_name;
+      return candidates;
+    }
+  }
 
   // Ok - all mandatory checked and we still have candidates.
   // Let's try filtering using the optional constraints. The optional
@@ -405,7 +408,7 @@ void MediaStreamVideoSource::AddTrack(
     case ENDED:
     case STARTED: {
       // Currently, reconfiguring the source is not supported.
-      FinalizeAddTrack();
+      FinalizeAddTrack(MEDIA_DEVICE_OK, "");
     }
   }
 }
@@ -457,12 +460,15 @@ void MediaStreamVideoSource::OnSupportedFormats(
   DCHECK_EQ(RETRIEVING_CAPABILITIES, state_);
 
   supported_formats_ = formats;
+  blink::WebString unsatisfied_constraint;
   if (!FindBestFormatWithConstraints(supported_formats_,
-                                     &current_format_)) {
+                                     &current_format_,
+                                     &unsatisfied_constraint)) {
     SetReadyState(blink::WebMediaStreamSource::ReadyStateEnded);
     // This object can be deleted after calling FinalizeAddTrack. See comment
     // in the header file.
-    FinalizeAddTrack();
+    FinalizeAddTrack(MEDIA_DEVICE_CONSTRAINT_NOT_SATISFIED,
+                     unsatisfied_constraint);
     return;
   }
 
@@ -484,7 +490,8 @@ void MediaStreamVideoSource::OnSupportedFormats(
 
 bool MediaStreamVideoSource::FindBestFormatWithConstraints(
     const media::VideoCaptureFormats& formats,
-    media::VideoCaptureFormat* best_format) {
+    media::VideoCaptureFormat* best_format,
+    blink::WebString* unsatisfied_constraint) {
   DCHECK(CalledOnValidThread());
   // Find the first constraints that we can fulfill.
   for (std::vector<RequestedConstraints>::iterator request_it =
@@ -501,7 +508,7 @@ bool MediaStreamVideoSource::FindBestFormatWithConstraints(
       return true;
     }
     media::VideoCaptureFormats filtered_formats =
-        FilterFormats(requested_constraints, formats);
+        FilterFormats(requested_constraints, formats, unsatisfied_constraint);
     if (filtered_formats.size() > 0) {
       // A request with constraints that can be fulfilled.
       GetBestCaptureFormat(filtered_formats,
@@ -513,10 +520,10 @@ bool MediaStreamVideoSource::FindBestFormatWithConstraints(
   return false;
 }
 
-void MediaStreamVideoSource::OnStartDone(bool success) {
+void MediaStreamVideoSource::OnStartDone(MediaStreamRequestResult result) {
   DCHECK(CalledOnValidThread());
-  DVLOG(3) << "OnStartDone({success =" << success << "})";
-  if (success) {
+  DVLOG(3) << "OnStartDone({result =" << result << "})";
+  if (result == MEDIA_DEVICE_OK) {
     DCHECK_EQ(STARTING, state_);
     state_ = STARTED;
     SetReadyState(blink::WebMediaStreamSource::ReadyStateLive);
@@ -526,10 +533,12 @@ void MediaStreamVideoSource::OnStartDone(bool success) {
 
   // This object can be deleted after calling FinalizeAddTrack. See comment in
   // the header file.
-  FinalizeAddTrack();
+  FinalizeAddTrack(result, "");
 }
 
-void MediaStreamVideoSource::FinalizeAddTrack() {
+void MediaStreamVideoSource::FinalizeAddTrack(
+    MediaStreamRequestResult result,
+    const blink::WebString& result_name) {
   DCHECK(CalledOnValidThread());
   media::VideoCaptureFormats formats;
   formats.push_back(current_format_);
@@ -538,17 +547,7 @@ void MediaStreamVideoSource::FinalizeAddTrack() {
   callbacks.swap(requested_constraints_);
   for (std::vector<RequestedConstraints>::iterator it = callbacks.begin();
        it != callbacks.end(); ++it) {
-    // The track has been added successfully if the source has started and
-    // there are either no mandatory constraints and the source doesn't expose
-    // its format capabilities, or the constraints and the format match.
-    // For example, a remote source doesn't expose its format capabilities.
-    bool success =
-        state_ == STARTED &&
-        ((!current_format_.IsValid() && !HasMandatoryConstraints(
-            it->constraints)) ||
-         !FilterFormats(it->constraints, formats).empty());
-
-    if (success) {
+    if (result == MEDIA_DEVICE_OK) {
       int max_width;
       int max_height;
       GetDesiredMaxWidthAndHeight(it->constraints, &max_width, &max_height);
@@ -572,10 +571,10 @@ void MediaStreamVideoSource::FinalizeAddTrack() {
                                on_mute_callback);
     }
 
-    DVLOG(3) << "FinalizeAddTrack() success " << success;
+    DVLOG(3) << "FinalizeAddTrack() result " << result;
 
     if (!it->callback.is_null())
-      it->callback.Run(this, success);
+      it->callback.Run(this, result, result_name);
   }
 }