Don't use SDK variant for vendor JNI libraries

Vendor JNI libraries already have stable APIs enforced by the VNDK,
they shouldn't use SDK variants.

Bug: 156225490
Test: TestJNISDK
Change-Id: I21ba67e8e9fb05016caf5888129adc1a939545c2
diff --git a/java/java.go b/java/java.go
index de38b26..17b963f 100644
--- a/java/java.go
+++ b/java/java.go
@@ -95,8 +95,7 @@
 }
 
 func (j *Module) checkSdkVersions(ctx android.ModuleContext) {
-	if j.SocSpecific() || j.DeviceSpecific() ||
-		(j.ProductSpecific() && ctx.Config().EnforceProductPartitionInterface()) {
+	if j.RequiresStableAPIs(ctx) {
 		if sc, ok := ctx.Module().(sdkContext); ok {
 			if !sc.sdkVersion().specified() {
 				ctx.PropertyErrorf("sdk_version",