Matthew Waters authored Jul 23, 2018 and Edward Hervey committed Nov 07, 2018

Use the bitrate advertised by queue2 to determine the limits to
set across possibly multiple queue2/downloadbuffer elements.  e.g.
with two queue2's and a max-bytes based on the ratio of the
bitrate/cumulative_bitrate multiplied by the buffer_size set on urisourcebin.

This allows finer grained control over the buffer used by all the queue
elements inside urisourcebin.  Instead of a maximum of
n_streams*buffer_size being used, only buffer_size will be used however
we will fallback to n_streams*buffer_size if one of the queue2's does
not have bitrate information.

gstreamer/gst-plugins-base#60