Make mainline API defs visible to CTS.

These API definitions need to be used by CTS tests so that can assert
things about the mainline API surface differently to the non-updatable
API surface.

Bug: 153997280
Test: m
Change-Id: I275fed235c879c7519c131119ac9384d1aef75d9

core/api/Android.bp

@@ -51,11 +51,17 @@ filegroup {
 filegroup {
     name: "non-updatable-module-lib-current.txt",
     srcs: ["module-lib-current.txt"],
-    visibility: ["//frameworks/base/api"],
+    visibility: [
+        "//frameworks/base/api",
+        "//cts/tests/signature/api",
+    ],
 }
 
 filegroup {
     name: "non-updatable-module-lib-removed.txt",
     srcs: ["module-lib-removed.txt"],
-    visibility: ["//frameworks/base/api"],
+    visibility: [
+        "//frameworks/base/api",
+        "//cts/tests/signature/api",
+    ],
 }