Fix click error due to undefined listener object

[wouterz]

Checking if listeners is defined before accessing property and removing. Before setting new properties set empty object if it is undefined.

This is also noted in issue #407 . But does not include setting new listeners

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[wouterz]

I signed it!

[googlebot]

CLAs look good, thanks!

[iuliaL]

Can you please merge this pr? Would be awesome. My app breaks due to this undefined.

[wouterz]

Almost 4 years later, this still seems to be an issue. Any chance of this getting merged?