stagefright: move MediaDefs from libstagefright to libmedia

Bug: 24761407
Change-Id: If4914340a645c6f3c14eea0c873c162926d72ca2
(cherry picked from commit ce4df5e534eb86748fe80c84efb6b7fc0b6b5b46)
diff --git a/media/libmedia/Android.mk b/media/libmedia/Android.mk
index 4379b10..109fada 100644
--- a/media/libmedia/Android.mk
+++ b/media/libmedia/Android.mk
@@ -24,6 +24,7 @@
     IResourceManagerService.cpp \
     IStreamSource.cpp \
     MediaCodecInfo.cpp \
+    MediaDefs.cpp \
     MediaUtils.cpp \
     Metadata.cpp \
     mediarecorder.cpp \