Build android.hardware.drm@1.0-service with BOARD_VNDK_VERSION

Instead of relying on the global include paths, use the new headers lib
'media_plugin_headers'. Also, media/SharedLibrary.h is not used, thus deleted.

Bug: 37342627
Test: BOARD_VNDK_VERSION=current m -j android.hardware.drm@1.0-service
Change-Id: I30d8bcb6315b734cef7ad082c432da51eb33119c
diff --git a/drm/1.0/default/Android.mk b/drm/1.0/default/Android.mk
index 0cc6e71..99773be 100644
--- a/drm/1.0/default/Android.mk
+++ b/drm/1.0/default/Android.mk
@@ -42,6 +42,9 @@
 LOCAL_C_INCLUDES := \
   hardware/interfaces/drm
 
+LOCAL_HEADER_LIBRARIES := \
+  media_plugin_headers
+
 # TODO(b/18948909) Some legacy DRM plugins only support 32-bit. They need to be
 # migrated to 64-bit. Once all of a device's legacy DRM plugins support 64-bit,
 # that device can turn on TARGET_ENABLE_MEDIADRM_64 to build this service as