Follow input changes to proptools.CloneEmptyProperties

Test: m checkbuild
Change-Id: I1fd53d03722d134009f7ed663f05bd6dc5980dd1
diff --git a/android/variable_test.go b/android/variable_test.go
index 751677f..cde2b1a 100644
--- a/android/variable_test.go
+++ b/android/variable_test.go
@@ -159,15 +159,15 @@
 func TestProductVariables(t *testing.T) {
 	ctx := NewTestContext()
 	// A module type that has a srcs property but not a cflags property.
-	ctx.RegisterModuleType("module1", testProductVariableModuleFactoryFactory(struct {
+	ctx.RegisterModuleType("module1", testProductVariableModuleFactoryFactory(&struct {
 		Srcs []string
 	}{}))
 	// A module type that has a cflags property but not a srcs property.
-	ctx.RegisterModuleType("module2", testProductVariableModuleFactoryFactory(struct {
+	ctx.RegisterModuleType("module2", testProductVariableModuleFactoryFactory(&struct {
 		Cflags []string
 	}{}))
 	// A module type that does not have any properties that match product_variables.
-	ctx.RegisterModuleType("module3", testProductVariableModuleFactoryFactory(struct {
+	ctx.RegisterModuleType("module3", testProductVariableModuleFactoryFactory(&struct {
 		Foo []string
 	}{}))
 	ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {