Rename session classes to have media prefix, hide routes

This renames several of the core session classes to be prefixed
with Media. It also adds @hide to all route references for now.

Change-Id: Idb42897d490cf24626e4e93ca975b2cb93ec054c
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 4eac802..da82060 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -2079,7 +2079,7 @@
 
     <!-- Must be required by a {@link android.media.routeprovider.RouteProviderService}
          to ensure that only the system can interact with it.
-         -->
+         @hide -->
     <permission android:name="android.permission.BIND_ROUTE_PROVIDER"
         android:label="@string/permlab_bindRouteProvider"
         android:description="@string/permdesc_bindRouteProvider"