Suppress the missing Executor lint warning

Android API guidelines require an Executor overload for methods that
accept a callback.  The three "beginTransactionWithListener" methods
do not have such an overload and these have been flagged by lint.

However, Executor is not suitable for these listener objects, since
the listeners expect to use thread-local variables.  It would be a
functional error to have the callback execute on any thread but the
current thread.

This commit suppresses the lint warning associated with the three
APIs; the @SuppressLint annotation serves as documentation that these
APIs will never use Executors.  The commit also removes the TODO
comments that were attached to the API.

Test: presubmit (verified that the lint warning is not present)
Flag: DOCS_ONLY
Bug: 340874899
Change-Id: Id2edc4c90f6b4aaf939705af0ac1ebdb17fcf854