Exit split if got request split when invisble

If split A/B then go home, and running A/B again or A/C as new
pair, it would be failed due to we could cover such case on current
implementation.

For fixing such cases, we still need to exit split first.

Fix: 262416120
Test: manual
Test: atest NexusLauncherTests:com.android.quickstep.TaplTestsTaskbar
Change-Id: I37a41ed5a87466652d7b052bc5e3b1c5627b973a