removeEventListener obj parameter not set as optional

[galaddirie]

The current type definition for removeEventListener in js/lib/cep/CSInterface.removeEventListener does not mark the obj parameter as optional.

The method documentation indicates that the obj parameter is optional (similar to addEventListener). suggesting the correct definition should look like this:

removeEventListener(type: any, listener: any, obj?: any): void;

Currently, the method is defined as:

removeEventListener(type: any, listener: any, obj: any):