[code-reflection] RFR: Support storing the code that builds the code model [v18]

[Mourad Abbay]

> In this PR we allow the user to decide how to store the code model. The first option is `TEXT`, if this is selected, we store the textual representation of the code model. The second option is `CODE_BUILDR`, if this is selected, we store the code that builds the code model. All work done here is around the second option, because the first option is already supported.

Mourad Abbay has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 20 additional commits since the last revision:

 - Merge branch 'code-reflection' into code-model-storage-option
 - Load OpFactory and TypeElementFactory before invocation of opMethod only if the opMethod has there params.
 - Fix the remaining compiler tests failures
 - Fix some of the test failures (3 remains)
 - Fix the remaining test failures of SwitchExpressionTest2
 - Fix almost all test failures of SwitchExpressionTest2 (one remaining)
 - Pass arrayType instead of eleType in OpBuilder.buildArray
 - Ensure that block params are inserted in the correct order
 - Add missing imports
 - Merge branch 'code-reflection' into code-model-storage-option
 - ... and 10 more: https://git.openjdk.org/babylon/compare/ddc18534...966005ce

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Changes:
  - all: https://git.openjdk.org/babylon/pull/305/files
  - new: https://git.openjdk.org/babylon/pull/305/files/0e49cceb..966005ce

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=305&range=17
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=305&range=16-17

  Stats: 24999 lines in 272 files changed: 18963 ins; 5180 del; 856 mod
  Patch: https://git.openjdk.org/babylon/pull/305.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/305/head:pull/305

PR: https://git.openjdk.org/babylon/pull/305