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/paths.go b/android/paths.go
index e457959..6322f75 100644
--- a/android/paths.go
+++ b/android/paths.go
@@ -94,6 +94,7 @@
 	EarlyModulePathContext
 	VisitDirectDepsBlueprint(visit func(blueprint.Module))
 	OtherModuleDependencyTag(m blueprint.Module) blueprint.DependencyTag
+	HasMutatorFinished(mutatorName string) bool
 }
 
 // ModuleMissingDepsPathContext is a subset of *ModuleContext methods required by