Removed the logic in MuxerListener to estimate bandwidth from file
size and duration, since it is not compliant to the spec.
MpdBuilder will estimate bandwidth from segment size and duration
if bandwidth is not specified in MediaInfo.
Here is the statement from DASH spec (23009-1:2014):
Consider a hypothetical constant bitrate channel of
bandwidth with the value of this attribute in bits per second
(bps). Then, if the Representation is continuously delivered
at this bitrate, starting at any SAP that is indicated either by
@startwithsap or by any Segment Index box, a client can
be assured of having enough data for continuous playout
providing playout begins after @minbuffertime *
@bandwidth bits have been received (i.e. at time
@minbuffertime after the first bit is received).
For dependent Representations this value specifies the
bandwidth according to the above definition for the
aggregation of this Representation and all complementary
Representations.
Fixes#376.
Change-Id: I0fddce39e709d0cded0a4c9ae59adbbcc97ec5ea
b2932d5a33