Avoid resolving split for activities that requested launching TF

The launching activity is resolved to the existing split rules
before invokes #startActivity and also when the activity is created.

However, this is not necessary if the app has requested the activity
to be launched into a specific TaskFragment in the first place.

Bug: 267955577
Test: verified on demo app
Test: SplitControllerTest
Change-Id: If61ad7bc5309a7adffff580d87a7d38aae65b0c6