Revert "API flagging macro until/starting_at for private and public"

This reverts commit d90d5ce422668a8ad33796c3b4f6910d360fdea5.

Reason for revert: Build broken

Change-Id: I3a74055f4d0d85ab576260594ce579c6705df3ba
diff --git a/build/soong/policy.go b/build/soong/policy.go
index 29685ea..4476f94 100644
--- a/build/soong/policy.go
+++ b/build/soong/policy.go
@@ -225,7 +225,17 @@
 }
 
 func (c *policyConf) boardApiLevel(ctx android.ModuleContext) string {
-	return ctx.Config().VendorApiLevel()
+	level := proptools.StringDefault(c.properties.Board_api_level, "system")
+
+	if level == "system" {
+		// aribtrary value greater than any other vendor API levels
+		return "1000000"
+	} else if level == "vendor" {
+		return ctx.Config().VendorApiLevel()
+	} else {
+		return level
+	}
+
 }
 
 func findPolicyConfOrder(name string) int {