Add test preparer for phony module types

... so that other tests can use the module type

Bug: N/A
Test: N/A (see the next change)
Change-Id: Ie71e4c67a5615809784c27e9834f7d818a4b649d

phony/phony.go

@@ -23,10 +23,16 @@ import (
 )
 
 func init() {
-	android.RegisterModuleType("phony", PhonyFactory)
-	android.RegisterModuleType("phony_rule", PhonyRuleFactory)
+	registerPhonyModuleTypes(android.InitRegistrationContext)
 }
 
+func registerPhonyModuleTypes(ctx android.RegistrationContext) {
+	ctx.RegisterModuleType("phony", PhonyFactory)
+	ctx.RegisterModuleType("phony_rule", PhonyRuleFactory)
+}
+
+var PrepareForTestWithPhony = android.FixtureRegisterWithContext(registerPhonyModuleTypes)
+
 type phony struct {
 	android.ModuleBase
 	requiredModuleNames       []string