- `is_valid_to_decode`: Implies at least one mix in the test vector can be decoded.
    - A compliant decoder should be able to find and decode a valid mix.
  - `is_valid`: Implies all mixes in the the test vector could be decoded.
    - The encoder will more strictly prevent encoding certain types of reserved fields which is not aware of.
    - This maintains the safety rails on the encoder which prevent it from using certain types of extension fields under normal circumstances.
    - May be used to prevent other types of reserved fields in the future.
    - May rename to `is_valid_to_encode` in the future.
  - `test_summary.csv`: Add a column for `is_valid_to_decode`.
  - The concepts are identical for test vectors with only one mix presentation (most of the test suite).
    - Hence, most existing test vectors have matching `is_valid` and `is_valid_to_decode`.
  - The concepts are distinguished when there is one valid mix and one invalid mix (i.e. `test_000120`, `test_000122`, `test_000129`, `test_000130`).
    - Typically we want safety rails and do not want to accidentally encode strange mixes that will never be decoded.

…ld be decoded.

  - `README.md`: Clarify since the spec does not determine behavior when something is invalid IAMF that a production system may still try to find a robust way to handle "should-fail" cases.
  - `test_000017`: Document the encoder may have a bug where it is too strict with `num_samples_to_trim_at_end`.
  - `test_000026`: Encoder refuses to produce it because "Output Channel Count SHALL be set to 2", but the decoder should process it anyway because "Output Channel Count can be ignored ".
  - `test_000119`: Encoder refuses to produce it because the codec ID is not known, but the decoder can ignore the mix related to that codec.
  - `test_000502`: Encoder refuses to produce it because `num_submixes` "SHALL NOT be set to 0", but the decoder can process the other mix.
  - Files based on AOMediaCodec/iamf-tools@468eb9b4

…belong in.

  - Mostly intended to help with bookeeping and scripts which are used to generare the test report, and decide which tests to run.
  - But secondarily this helps tag tests that are relevant if a private implementer wants to examine tests based on particular versions of IAMF.
  - The tags match any branches the test vector will be maintained in - this is useful if future bugs are fixed that require regenerating tests.
  - Based on AOMediaCodec/iamf-tools@a104c1cf9.

…10 spec.

  - Resolves both parts A and B in AOMediaCodec#119 for the test vectors.
    - Part A: Add missing "expandable" size field to both of the `DecoderConfigDescriptor` and `DecoderSpecificInfo`.
    - Part B: Flip `DecoderConfigDescriptor` `reserved` bit to 1.
    - Based on AOMediaCodec/iamf-tools@57324193.

Generated file based on AOMediaCodec/iamf-tools@1d2e00a