don't lose track of private data in the ACC tests

This commit was generated from hashicorp/terraform#22837.

Author: jbardin

helper/resource/state_shim.go

@@ -81,9 +81,10 @@ func shimNewState(newState *states.State, providers map[string]terraform.Resourc
 					}
 
 					if i.Current.SchemaVersion != 0 {
-						resState.Primary.Meta = map[string]interface{}{
-							"schema_version": i.Current.SchemaVersion,
+						if resState.Primary.Meta == nil {
+							resState.Primary.Meta = map[string]interface{}{}
 						}
+						resState.Primary.Meta["schema_version"] = i.Current.SchemaVersion
 					}
 
 					for _, dep := range i.Current.Dependencies {