MetadataStorage is mutable - structural equals in copy isn't enough

[JaroslavTulach]

Pull Request Description

MetadataStorage is mutable. Using Object.equals in IR.copy methods to check whether a copy is needed isn't enough. The fact that two storages are Object.equal may be just temporary. Replacing the checks in 69 IR.copy methods with identity check - e.g. ne in Scala which is == in Java.

Using proper structural check inside of MetadataStorage fixes #11171.

Important Notes

I used this regex to find out 69 instances of IR.copy:

and I modified all 69 of them.

Checklist

Please ensure that the following checklist has been satisfied before submitting the PR:

• All code follows the
  Scala,
  Java,
• Unit tests should be updated to new behavior of MetadataStorage.equals