Add uninstall option in the capabilities confirm dialog

Uninstall option is visible only when the application of the
service is not system App. It provides an efficient way to
uninstall the App if users are shocked with the perimssions
they need to grant.

Bug: 176877955
Test: Install an App with AccessibilityService and uninstall
it with this option.

Change-Id: I6b60cc56d8d34c2983458a676b500035551ec9df