[code-reflection] Integrated: Simplify creation of BoundSchema from Schema

[Gary Frost]

Previously we have a Schema, where a Schema is a static description of a iface mapping. So it captures the types, the order and the relationship between fields. 

We don't want to create a new Schema when only the size of arrays differ.  

When we need real layout information we need to provide 'dimensions' for arrays which were unbound in the static schema. 

So before we allocate we create a BoundSchema this fills in the previously empty array dims and from this, we can create layouts .

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Commit messages:
 - Simplify creation of BoundSchema from Schema

Changes: https://git.openjdk.org/babylon/pull/163/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=163&range=00
  Stats: 618 lines in 7 files changed: 252 ins; 164 del; 202 mod
  Patch: https://git.openjdk.org/babylon/pull/163.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/163/head:pull/163

PR: https://git.openjdk.org/babylon/pull/163