Move deferred task info logic to callback

This CL moves the logic of deferred task info to transition callback so
a derived class of PipTaskOrg can use the same logic without accessing
the private functions of PipTaskOrg.

Also, this CL makes some menber variables of PipTaskOrg protected so a
derived class can implement dismiss-pip by itself.

Bug: 238973789
Test: m
Change-Id: If980a6c08dc5e1a5d695bb53d7963cd2442aff08
(cherry picked from commit 53d88c2e0417dde76a03b0f261322470f0ac2edd)