Fill OpenSL-ES producer buffer with custom audio samples

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What steps will reproduce the problem?
1.
2.
3.

What is the expected output? What do you see instead?
This is a feature request:
Add a feature for OpenSL-ES plugin like the fillPushBuffer at:
http://code.google.com/p/imsdroid/source/browse/branches/2.0/android-ngn-stack/s
rc/org/doubango/ngn/media/NgnProxyAudioProducer.java#137

Such feature could be useful to send samples from custom audio track (i.e. from
a wav file) instead of mic also if OpenSL-ES plugin is used.

What version of the product are you using? On what operating system?

Please provide any additional information below.
This feature is already available if ProxyAudioProducer is used but not for the
OpenSL-ES plugin.

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Original issue reported on code.google.com by `massimo....@gmail.com` on 13 Jan 2014 at 8:28

Start by comparing the OpenSL-ES plugin with the referenced fillPushBuffer implementation in NgnProxyAudioProducer.java. Trace how the OpenSL-ES producer currently obtains microphone samples, then verify that the requested behavior—supplying custom samples such as WAV data instead—is supported and covered by an appropriate test or reproducible check.

Written by the indexing model from the issue text.