* LiteralEventChainVar becomes an ArgsFunctionOperation
Instead of using the ArgsFunctionOperation to create the string representation
of the _js_expr, make the identity of the var an ArgsFunctionOperation so the
_args_names and _return_expr remain accessible.
Rely on the default behavior of ArgsFunctionOperation to create the
_cached_var_name / _js_expr value.
This allows the compat shim in `format_event_chain` to remain functional, as it
does special handling for ArgsFunctionOperation to retain the previous behavior
of that function (this was a regression introduced in 0.6.2).
* _var_type is EventChain; fix parent class order
* Re-fix LiteralEventChainVar inheritence list w/ comment
* [ENG-3942] LiteralEventVar becomes VarCallOperation
instead of using `.call` when constructing the `_js_expr`, have the identity of
a LiteralEventVar as a VarCallOperation to take advantage of the _var_data
carrying.
* add event overlords
* EventCallback descriptor always returns EventSpec from class
Relax actual `__get__` definition to support the multitude of overloads
* test case for event related vars carrying _var_data
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Co-authored-by: Khaleel Al-Adhami <khaleel.aladhami@gmail.com>
c460040040