Track transitive usage of aconfig flags and add LOCAL_ACONFIG_FILES to Android-<product>.mk

Bug: 283910439
Test: m nothing (runs soong tests)
Change-Id: I59f9bef7b7c502565d531a5685c002a177e0a77c

java/device_host_converter.go

@@ -143,6 +143,8 @@ func (d *DeviceHostConverter) GenerateAndroidBuildActions(ctx android.ModuleCont
 		ResourceJars:                   d.resourceJars,
 		SrcJarArgs:                     d.srcJarArgs,
 		SrcJarDeps:                     d.srcJarDeps,
+		// TODO: Not sure if aconfig flags that have been moved between device and host variants
+		// make sense.
 	})
 
 }