Purge cache when the server removes the policy for an extension.

components/policy/core/common/cloud/mock_cloud_policy_client.h

Index: components/policy/core/common/cloud/mock_cloud_policy_client.h
diff --git a/components/policy/core/common/cloud/mock_cloud_policy_client.h b/components/policy/core/common/cloud/mock_cloud_policy_client.h
index 3d4b2bba57b02816484e266e7bb02d1110d10a42..b4640a5d26ea1dfe32e8d33a1fda59de2b01aa0c 100644
--- a/components/policy/core/common/cloud/mock_cloud_policy_client.h
+++ b/components/policy/core/common/cloud/mock_cloud_policy_client.h
@@ -51,6 +51,7 @@ class MockCloudPolicyClient : public CloudPolicyClient {
   using CloudPolicyClient::public_key_version_;
   using CloudPolicyClient::public_key_version_valid_;
   using CloudPolicyClient::namespaces_to_fetch_;
+  using CloudPolicyClient::namespaces_requested_;
   using CloudPolicyClient::invalidation_version_;
   using CloudPolicyClient::invalidation_payload_;
   using CloudPolicyClient::fetched_invalidation_version_;