p-sidebar dimissable flag is not re-evaluated when its value changes

[thaihacong]

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Plunkr Case (Bug Reports)
https://stackblitz.com/edit/github-qbafbn?file=src%2Fapp%2Fapp.component.html

Current behavior
I have a p-sidebar as follow

<p-sidebar [(visible)]="display" position="right" 
             [dismissible]="!changed"
             [showCloseIcon]="!changed">

When changed flag is updated, only closeIcon is shown/hidden correspondingly, but value of dismissible flag is evaluated only once on initialization.
On my given plunkr, changed = false on init, therefore dismissible = true, user can always click outside to close the sidebar, although changed = true later (on click).

Expected behavior
dismissible flag should be re-evaluated every time its value changed.

Minimal reproduction of the problem with instructions
Click Show/hide sidebar to open sidebar, then click Toggle changed flag and click outside to check if the sidebar is dimissible or not.

What is the motivation / use case for changing the behavior?
I have sidebar as an edit dialog, it should not be dimissible when user has unsaved changes.

• Angular version: 7.2.0

• PrimeNG version: 7.0.4