Retrieve hiddenapi-flags.csv from platform-bootclasspath

Test: m CtsHiddenApiBlocklistTestApiTestCases
      Run it with and without this change and ensure that the contents
      of the APK are not affected.
Bug: 177892522
Change-Id: I662bc94baf083ea5dc995e09f2bad02d9db2b78f
diff --git a/tests/signature/api-check/Android.bp b/tests/signature/api-check/Android.bp
index 3f686c2..5e7ff3b 100644
--- a/tests/signature/api-check/Android.bp
+++ b/tests/signature/api-check/Android.bp
@@ -70,12 +70,6 @@
     static_libs: ["cts-api-signature-test"],
 }
 
-// Access the hiddenapi-flags.csv file produced by the build.
-hiddenapi_flags {
-    name: "cts-hiddenapi-flags-csv",
-    filename: "hiddenapi-flags.csv",
-}
-
 filegroup {
     name: "cts-api-hiddenapi-filter-csv",
     srcs: [
@@ -88,7 +82,7 @@
     name: "hiddenapi-blocklist-check-defaults",
     defaults: ["signature-api-check-defaults"],
     java_resources: [
-        ":cts-hiddenapi-flags-csv",
+        ":platform-bootclasspath{hiddenapi-flags.csv}",
         ":cts-api-hiddenapi-filter-csv"
     ],
     jni_libs: [