Stagefright: Make classes customizable and add AV extensions

Change access modifiers and qualify methods with virtual, to
allow extensions. Add facility for loading customizations
(Extended classes) dynamically

Below chages are squashed with this change

 nuplayer: Do not drop corrupt EOS frame
 Change-Id: Ib231dd8eb89aa14f824760562fcc371246d7ba9d

 libstagefright: Allow for MPEG4Writer extension
 Change-Id: If0918be77ab7f8d82c78203f371df789e3cc29b8

 nuplayer: Drop frames with DATACORRUPT flag
 Change-Id: I97bd238d52d660e1ab61eac222cdff28334cc5cc

 libstagefright: choose target specific media_codecs_performance.xml
 Change-Id: If3b37877a38cce59e074f7399c8a844c7cfe55a9

 video: Port miscellaneous video framework changes
 89c6c3f libstagefright: Allocate cached camera buffers for sw encoders
 Change-Id: I90398b2fead1f4e163935bf1db342e24275f7933

 libstagefright: Allow for CameraSourceTimeLapse to be extended
 Change-Id: I309a247ba6e3c5626cfba096677a6dbfeae543f3

 stagefright: Remove additional deep-copy of encoder buffers
 Change-Id: Ib59ac29ebc6ce4afd6fc272688a8260438ab1517

 libstagefright: Set Intra period
 Change-Id: Id2b3e71b746eaaed76118126d44ad83458d68520

 video: Port miscellaneous video framework changes
 Except 89c6c3f libstagefright: Allocate cached camera buffers for sw encoders
 Change-Id: I90398b2fead1f4e163935bf1db342e24275f7933

 avextensions: Add support for Codec Extension features
 Change-Id: Ia342d4abe4bb1e21b9ff2b8213fb96421485a333

 frameworks/av: Changes related to DASH
 Change-Id: I0376841530218703fabd9d4f45d2c9a32a1f52b2

 stagefright: Add support for custom size i/p buffer
 Change-Id: Iad31f5c85601983b01e18e130b1c3eecb3988e30

 audio: use updated method for getting sample bits
 Change-Id: Ic0620fd009a8544db138f088cfd2e7e4a4ff390c

 libmedia: fix for underrun and gapless issue.
 Change-Id: I1ad25d3789aced6b804aa695485341bfa4e97eae

 audio: add support for HW AAC encoder
 Change-Id: I08279fb077f4675736ed76d26c2681a2d1776aab

 libstagefright: Add mime type for VC1 codec
 Change-Id: Id9110ad20eba4d1a053d058d496637e91feb3a35

 stagefright: Update extended extractor APIs
 Change-Id: If8cfc9cff9dd48fbe764f438463c3e24763d4f44

 libstagefright: Update extractor for specific formats
 Change-Id: I63dcc4b2d3901dbc3287eb43a1f4ce2767897258

 audio: add support for wma-pro wma-lossless decoding
 Change-Id: I73ae2c2ccabafebc49d4b2e074da23cb4e51a3ce

 audio: add support for vorbis offloading
 Change-Id: Ic51a9d3e0fad1114908f59bfbc6ce62c6fd9fdea

 AVCustomizations: include audio header files explicitly
 Change-Id: Ib30f94c2b4540a3dbfd2388f43f5d229be047ec7

 audio: add support for APE decoding
 Change-Id: I55e8f4b3b87f4bdf1c99774d702506eb7c2f05b5

 audio: add support for AMRWB+
 Change-Id: I6eedebe93c482150234b4ca1d0472b189c450dc6

 audio: add WMA formats in MediaDefs
 Change-Id: Ifefe04647071eee04ab1e746436fec056ece689f

 audio: add support for offload FLAC
 Change-Id: I617b41b867277272212d6cf1a6f82f646c5b1032

Conflicts:
	include/media/stagefright/ACodec.h
	media/libmediaplayerservice/StagefrightRecorder.h
	media/libstagefright/DataSource.cpp
	media/libstagefright/MediaCodec.cpp
	media/libstagefright/Utils.cpp

Conflicts:
	media/libmediaplayerservice/MediaPlayerService.cpp
	media/libmediaplayerservice/MediaRecorderClient.cpp
	media/libmediaplayerservice/MetadataRetrieverClient.cpp
	media/libmediaplayerservice/StagefrightRecorder.cpp
	media/libstagefright/ACodec.cpp
	media/libstagefright/codecs/aacdec/SoftAAC2.cpp

Change-Id: Icc8965754fb1c73175a13a9ad24c19665ad60988