Add EAC3 support to MediaExtractor

Report EAC3 mime, sample-rate and channel count
for MPEG4 and TS.

This commit supersedes the commit on  p-fs-release  branch.
https://partner-android-review.googlesource.com/c/platform/frameworks/av/+/1057810



Change-Id: I9e14d821b5e78a03028bc52d8ee838c23859e9e9
Signed-off-by: Previr Rangroo <prang@dolby.com>