Remove top down mutators

Top down mutators are no longer used in Soong!

Bug: 367784740
Test: builds
Change-Id: I26114a2412277b82edafc4dc5849c3688d184361
diff --git a/android/mutator_test.go b/android/mutator_test.go
index 60a6119..123c6b2 100644
--- a/android/mutator_test.go
+++ b/android/mutator_test.go
@@ -54,7 +54,7 @@
 	ctx.AddDependency(ctx.Module(), nil, m.props.Deps_missing_deps...)
 }
 
-func addMissingDependenciesMutator(ctx TopDownMutatorContext) {
+func addMissingDependenciesMutator(ctx BottomUpMutatorContext) {
 	ctx.AddMissingDependencies(ctx.Module().(*mutatorTestModule).props.Mutator_missing_deps)
 }
 
@@ -72,7 +72,7 @@
 		FixtureRegisterWithContext(func(ctx RegistrationContext) {
 			ctx.RegisterModuleType("test", mutatorTestModuleFactory)
 			ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {
-				ctx.TopDown("add_missing_dependencies", addMissingDependenciesMutator)
+				ctx.BottomUp("add_missing_dependencies", addMissingDependenciesMutator)
 			})
 		}),
 		FixtureWithRootAndroidBp(bp),