Allowing launch cookies to be passed via pending activity starts

When overriding pending activity starts using remote animations,
we're now also allowing the passage of a launch cookie to associate
the task with the launched app. This allows us to return to the
right widgets for certain apps using broadcast trampolines.

Fixes: 220290671
Test: add Photos widget, return properly to widget
Change-Id: I339ea827836fa53ab5bb1617a72f9e0e5ae0f5ec