Select supports product_variable("eng")

Bug: 323382414
Bug: 387922915
Test: run soong test pass
Change-Id: Ic2975517c3837e4c8d05c0c5b91db48c9d34cabc
diff --git a/android/module.go b/android/module.go
index 9e620fb..2dd2f19 100644
--- a/android/module.go
+++ b/android/module.go
@@ -2494,6 +2494,8 @@
 			return proptools.ConfigurableValueBool(ctx.Config().BuildFromTextStub())
 		case "debuggable":
 			return proptools.ConfigurableValueBool(ctx.Config().Debuggable())
+		case "eng":
+			return proptools.ConfigurableValueBool(ctx.Config().Eng())
 		case "use_debug_art":
 			// TODO(b/234351700): Remove once ART does not have separated debug APEX
 			return proptools.ConfigurableValueBool(ctx.Config().UseDebugArt())