diff --git a/java/system_modules_test.go b/java/system_modules_test.go
index 336dd21..1a8d0b5 100644
--- a/java/system_modules_test.go
+++ b/java/system_modules_test.go
@@ -182,11 +182,7 @@
 	for _, tc := range testCases {
 		res := android.GroupFixturePreparers(
 			prepareForJavaTest,
-			android.FixtureModifyProductVariables(func(variables android.FixtureProductVariables) {
-				variables.BuildFlags = map[string]string{
-					"RELEASE_APEX_CONTRIBUTIONS_ADSERVICES": "myapex_contributions",
-				}
-			}),
+			android.PrepareForTestWithBuildFlag("RELEASE_APEX_CONTRIBUTIONS_ADSERVICES", "myapex_contributions"),
 		).RunTestWithBp(t, fmt.Sprintf(bp, tc.selectedDependencyName))
 
 		// check that rdep gets the correct variation of system_modules