Add a system_modules defn for core.current.stubs

The build system uses core-system-modules with
core.current.stubs, which is incorrect because
core-system-modules contains the implementation
code.

Test: EXPERIMENTAL_JAVA_LANGUAGE_LEVEL_9=true m droid java cts tests docs
Change-Id: Ibda795e829acee2d44ea1fcc2a07951443727cdf
diff --git a/JavaLibrary.bp b/JavaLibrary.bp
index 18a860f..42a0c2f 100644
--- a/JavaLibrary.bp
+++ b/JavaLibrary.bp
@@ -714,6 +714,22 @@
     },
 }
 
+// Used when compiling higher-level code against core.current.stubs.
+java_system_modules {
+    name: "core-current-stubs-system-modules",
+    libs: [
+        "core.current.stubs",
+        // This one is not on device but it's needed when javac compiles code
+        // containing lambdas.
+        "core-lambda-stubs-for-system-modules",
+        // This one is not on device but it's needed when javac compiles code
+        // containing @Generated annotations produced by some code generation
+        // tools.
+        // See http://b/123891440.
+        "core-generated-annotation-stubs",
+    ],
+}
+
 // Target for validating nullability annotations for correctness and
 // completeness. To check that there are no nullability errors:
 //   make core-current-stubs-nullability-validation