Fix for #520

[tkshnwesper]

Description

1. Fix for #520
2. Refactoring some code - like moving super.onCollision calls to the end of the method.

Checklist

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• [x] I open this PR to the develop branch.
• [x] I have added a description of the change under [next] in CHANGELOG.md.
• [x] I ran dart format --output=none --set-exit-if-changed . and has success.

Breaking Change

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[RafaelBarbosatec]

LGTM! Thank's só much for contributing!