Include sdk versioning proto in mediaprovider apex

Allows SdkExtensions to inspect its version to decide what the extension
sdk version is on-device.

Bug: 188787081
Test: m com.android.mediaprovider and inspect
Change-Id: Ieeab2fbb23520a37f0e387d96ed1ae59adfec6d0
diff --git a/apex/Android.bp b/apex/Android.bp
index cb6da5f..2668806 100644
--- a/apex/Android.bp
+++ b/apex/Android.bp
@@ -18,6 +18,7 @@
 apex_defaults {
     name: "com.android.mediaprovider-defaults",
     bootclasspath_fragments: ["com.android.mediaprovider-bootclasspath-fragment"],
+    prebuilts: ["current_sdkinfo"],
     key: "com.android.mediaprovider.key",
     certificate: ":com.android.mediaprovider.certificate",
     file_contexts: ":com.android.mediaprovider-file_contexts",