* Change native back button behavior in EC view:
- inject escape into webview instead of going back.
- the webview will call back when no other modal is open.
* call down and up in the webview + make sure that we fall back to close
pip in case the webview did not handle the esc action.
* Tests and refactor to CallScreenBackPressPolicy
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Co-authored-by: Jorge Martín <jorgem@element.io>
Timo
c959f50d53