Add null check when checking clipboard actions package

If a RemoteAction returned through TextClassifier does not have
a ComponentName set, it will cause an NPE. This change adds a
null check to forestall that (and just doesn't show a chip if
there's no ComponentName).

Bug: 218458652
Test: manual (force-set component to null and checked that error
occurred before but not after fix)

Change-Id: Ia17e2375f8a31b44de51e3cfb0dafc8c1dff1ad2