Add intent flags back to TaskInfo's base intent

- In ag/10502484 we cloned the task info's base intent
  filtering out the extras and data, but this also
  filters out the flags, which are used by the
  AppTaskTests to check whether it was actually marked
  as excluded. We can add it back to the task info
  since it doesn't cost anything.

Bug: 151123429
Test: atest CtsAppTestCases:AppTaskTests#testSetExcludeFromRecents

Change-Id: Ib616f63a3ed76d82a0e68149855568e7a6155b24