Use resource_id instead of phy res name OS::Heat::AutoScalingGroup

We now will uses resource_id instead of physical resource name when we use
get_resource in template.

If you run `get_resource: {physical autoscalinggroup_1}`, will now
return resource id for `autoscalinggroup_1`.

Change-Id: I71ec0f28d3c8251e776d014a38e6a1984daf52ae
Story: #2007007
Task: #37787

heat/engine/resources/openstack/heat/autoscaling_group.py

@@ -23,6 +23,7 @@ from heat.engine import constraints
 from heat.engine.hot import template
 from heat.engine import output
 from heat.engine import properties
+from heat.engine import resource
 from heat.engine.resources.aws.autoscaling import autoscaling_group as aws_asg
 from heat.engine import rsrc_defn
 from heat.engine import support
@@ -207,6 +208,9 @@ class AutoScalingResourceGroup(aws_asg.AutoScalingGroup):
                      self)._create_template(num_instances, num_replace,
                                             template_version=template_version)
 
+    def get_reference_id(self):
+        return resource.Resource.get_reference_id(self)
+
     def _attribute_output_name(self, *attr_path):
         return ', '.join(six.text_type(a) for a in attr_path)
 

releasenotes/notes/fix-autoscalinggroup-reference-id-caf8b80c9288ad0f.yaml

@@ -0,0 +1,9 @@
+---
+fixes:
+  - |
+    The behavior of ``get_resource`` on an ``OS::Heat::AutoScalingGroup``
+    resource has changed. Previously it returned the physical resource name
+    (i.e. the name of the nested Heat stack which implemented the group). It
+    will now return the UUID of the nested stack if available. This will also
+    apply to any resource type that inherits from
+    ``OS::Heat::AutoScalingGroup``.