The changes are to help users prepare for migration to next major
release (v8.0.0) regarding to the break change of realm order config.
Warnings are added for when:
* A realm does not have an order config
* Multiple realms have the same order config
The warning messages are added to both deprecation API and loggings.
The main reasons for doing this are: 1) there is currently no automatic relay
between the two; 2) deprecation API is under basic and we need logging
for OSS.