The progress bar of music player will not synchronize after seeking

[countrysideboy]

Some music players do not query the position all the time,when I change the progress bar,the music players transport seek command and gmrender reply a seekresponse,then the progress bar freeze until a lastchange notify is given by gmrender.

Gmrender reply a lastchange notify(such as TransportState val= PLAYING) after seekresponse will fix this bug.

The gst_element_seek function pause then play the song,but if my current state is pausing,the gmrender will play the song after seeking without sync the state.