Implement ConstraintNotSatisfiedError for getusermedia

content/renderer/media/media_stream_impl.h

 // Copyright (c) 2012 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_IMPL_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_IMPL_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 80 matching lines @@
   void OnLocalSourceStopped(const blink::WebMediaStreamSource& source);
 
   // These methods are virtual for test purposes. A test can override them to
   // test requesting local media streams. The function notifies WebKit that the
   // |request| have completed.
   virtual void GetUserMediaRequestSucceeded(
        const blink::WebMediaStream& stream,
        blink::WebUserMediaRequest* request_info);
   virtual void GetUserMediaRequestFailed(
       blink::WebUserMediaRequest* request_info,
-      content::MediaStreamRequestResult result);
+      content::MediaStreamRequestResult result,
+      const blink::WebString& result_name = blink::WebString());

[no longer working on chromium, 2014/07/25 19:27:35]

I don't understand why you need a result_name string here? why result is not
enough?
Also, adding a default param is not chromium style, what is your plan of
removing it?

[jiajia.qin, 2014/07/28 04:46:52]

The spec says if it is a constraint failure. Let error be a new MediaSteamError
object whose name attribute has the value ConstraintNotSatisfiedError and whose
constraintName attribute is set to the name of the constraint that caused the
error. Here, result is used to distinguish which error it is and result_name is
used to specify the constraintName if it is a ConstraintNotSatisfiedError.
Otherwise, the result_name will be set empty.
 
Here, result_name is used if the result is CONSTRAINT_NOT_SATISFIED_ERROR.
Otherwise, if the result is other error cases, we don't need to set result_name.
So, here I add a default param. 

   virtual void EnumerateDevicesSucceded(
       blink::WebMediaDevicesRequest* request,
       blink::WebVector<blink::WebMediaDeviceInfo>& devices);
   // Creates a MediaStreamVideoSource object.
   // This is virtual for test purposes.
   virtual MediaStreamVideoSource* CreateVideoSource(
       const StreamDeviceInfo& device,
       const MediaStreamSource::SourceStoppedCallback& stop_callback);
 
  private:
   // Class for storing information about a WebKit request to create a
   // MediaStream.
   class UserMediaRequestInfo
       : public base::SupportsWeakPtr<UserMediaRequestInfo> {
    public:
     typedef base::Callback<void(UserMediaRequestInfo* request_info,
-                                content::MediaStreamRequestResult result)>
+                                content::MediaStreamRequestResult result,
+                                const blink::WebString& result_name)>
       ResourcesReady;
 
     UserMediaRequestInfo(int request_id,
                          blink::WebFrame* frame,
                          const blink::WebUserMediaRequest& request,
                          bool enable_automatic_output_device_selection);
     ~UserMediaRequestInfo();
     int request_id;
     // True if MediaStreamDispatcher has generated the stream, see
     // OnStreamGenerated.
@@ skipping 13 matching lines @@
     // Triggers |callback| when all sources used in this request have either
     // successfully started, or a source has failed to start.
     void CallbackOnTracksStarted(const ResourcesReady& callback);
 
     bool IsSourceUsed(const blink::WebMediaStreamSource& source) const;
     void RemoveSource(const blink::WebMediaStreamSource& source);
 
     bool AreAllSourcesRemoved() const { return sources_.empty(); }
 
    private:
-    void OnTrackStarted(MediaStreamSource* source, bool success);
+    void OnTrackStarted(

[no longer working on chromium, 2014/07/28 19:55:08]

Avoid using default param.

If OnTrackStarted is used in many places, probably you should make a overload
OnTrackStarted method with const blink::WebString& result_name so that it won't
force all the clients to pass an empty string.

[jiajia.qin, 2014/07/30 05:18:07]

I have made a overload for GetUserMediaRequestFailed. For trackstarterror, it
will call GetUserMediaRequestFailed with const blink::WebString& result_name.
For other errors, keep the default function call.

+        MediaStreamSource* source,
+        content::MediaStreamRequestResult result,
+        const blink::WebString& result_name = blink::WebString());
     void CheckAllTracksStarted();
 
     ResourcesReady ready_callback_;
     bool request_failed_;
     // Sources used in this request.
     std::vector<blink::WebMediaStreamSource> sources_;
     std::vector<MediaStreamSource*> sources_waiting_for_callback_;
   };
   typedef ScopedVector<UserMediaRequestInfo> UserMediaRequests;
 
@@ skipping 30 matching lines @@
   void CreateAudioTracks(
       const StreamDeviceInfoArray& devices,
       const blink::WebMediaConstraints& constraints,
       blink::WebVector<blink::WebMediaStreamTrack>* webkit_tracks,
       UserMediaRequestInfo* request);
 
   // Callback function triggered when all native versions of the
   // underlying media sources and tracks have been created and started.
   void OnCreateNativeTracksCompleted(
       UserMediaRequestInfo* request,
-      content::MediaStreamRequestResult result);
+      content::MediaStreamRequestResult result,
+      const blink::WebString& result_name = blink::WebString());
 
   UserMediaRequestInfo* FindUserMediaRequestInfo(int request_id);
   UserMediaRequestInfo* FindUserMediaRequestInfo(
       const blink::WebUserMediaRequest& request);
   void DeleteUserMediaRequestInfo(UserMediaRequestInfo* request);
 
   MediaDevicesRequestInfo* FindMediaDevicesRequestInfo(int request_id);
   MediaDevicesRequestInfo* FindMediaDevicesRequestInfo(
       const blink::WebMediaDevicesRequest& request);
   void DeleteMediaDevicesRequestInfo(MediaDevicesRequestInfo* request);
@@ skipping 22 matching lines @@
 
   // Requests to enumerate media devices.
   MediaDevicesRequests media_devices_requests_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_IMPL_H_