Remove libmedia and libstagefright dependency from extractors

- MediaSource, DataSource and MediaExtractor are moved to
  libmediaextractor so that they can be used by extractor
  implementations without depending on libmedia and libstagefright.
- XXXFactory classes has been added in order not to expose CreateXXX
  methods in libmediaextractor.
- avc_utils is moved to libstagefright_foundation since most of
  extractor implementations are relying on that.

Test: build + post submit media CTS tests
Bug: 65851881
Change-Id: I7d5cf18dd25abc10478ac3f6e7d1828ad023e3fb
diff --git a/media/extractors/mp4/Android.bp b/media/extractors/mp4/Android.bp
index 52ddde4..c1e299e 100644
--- a/media/extractors/mp4/Android.bp
+++ b/media/extractors/mp4/Android.bp
@@ -13,8 +13,8 @@
 
     shared_libs: [
         "liblog",
-        "libmedia",
-        "libstagefright",
+        "libmediaextractor",
+        "libstagefright",  // Needed for ESDS
         "libstagefright_foundation",
         "libutils",
     ],