[IndexedDB] For schema mutations, should InvalidStateError trump TransactionInactiveError? (#23)

When calling {create,delete}{ObjectStore,Index} operations, FF throws `InvalidStateError` if there is not an active versionchange transaction, so TransactionInactiveError is never thrown by these methods.

Chrome distinguishes these cases.

The spec wording is slightly ambiguous.

TODO: Check IE and Safari.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/IndexedDB/issues/23