Extend sanitize_test.go

Test: go test soong cc tests
Change-Id: I63fe74fb837e25f63074fb918a573f8b421562f1
diff --git a/android/testing.go b/android/testing.go
index 8fcf440..29af71f 100644
--- a/android/testing.go
+++ b/android/testing.go
@@ -203,6 +203,10 @@
 	ctx.PreArchMutators(f)
 }
 
+func (ctx *TestContext) ModuleProvider(m blueprint.Module, p blueprint.ProviderKey) interface{} {
+	return ctx.Context.ModuleProvider(m, p)
+}
+
 func (ctx *TestContext) PreDepsMutators(f RegisterMutatorFunc) {
 	ctx.preDeps = append(ctx.preDeps, f)
 }