Add HasMutatorFinished

To enforce that selects are only evaluated after a certain point
in a followup cl.

Bug: 323382414
Test: m nothing --no-skip-soong-tests
Change-Id: Ib215fedb904aa2e5f4d65cfd26a23f527eb4983e
diff --git a/android/androidmk.go b/android/androidmk.go
index 98f8bb1..c175bec 100644
--- a/android/androidmk.go
+++ b/android/androidmk.go
@@ -502,6 +502,7 @@
 	otherModuleProvider(module blueprint.Module, provider blueprint.AnyProviderKey) (any, bool)
 	ModuleType(module blueprint.Module) string
 	OtherModulePropertyErrorf(module Module, property string, fmt string, args ...interface{})
+	HasMutatorFinished(mutatorName string) bool
 }
 
 func (a *AndroidMkEntries) fillInEntries(ctx fillInEntriesContext, mod blueprint.Module) {