[Validator] Add check for existing metadata on property
merged branch dlsniper/validator-check-property-metadata (PR #6972)

This PR was squashed before being merged into the 2.2 branch (closes #6972).

Commits
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4cbdbcb [Validator] Add check for existing metadata on property

Discussion
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[Validator] Add check for existing metadata on property

| Q             | A
| ------------- | ---
| Bug fix?      | no (sort of)
| New feature?  | no
| BC breaks?    | no (I don't think so)
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | ~
| License       | MIT
| Doc PR        | ~

Todo:
- [x] Check if the new method should be added to the interface as well.

This adds a check for metadata existence before usage else the code will emit a warning.

This should not be a BC break or a bug fix as the patched code is 2.2 specific.

@bschussek let me know if I should add the method in the interface as well. Thank you.

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by vicb at 2013-02-05T10:40:56Z

Strictly speaking this is a BC break (you are adding a public method). But I guess we should better defined what should be describe as BC break - I have asked myself the same question more than one time /cc @fabpot

Please also add a UT and a note in the changelog.

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by dlsniper at 2013-02-05T11:26:30Z

@vicb thanks for input. In this case I guess I should add the method to the interface as well.

As for unit tests I'll add them soon as well.

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by fabpot at 2013-02-05T14:19:14Z

Can you add a test?

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by dlsniper at 2013-02-05T15:57:12Z

I'll do it tonight as I've bumped into some work related issues.

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by fabpot at 2013-02-11T11:11:12Z

Just for the record, this is not a BC break as the interface was added in 2.2.