Show Taskbar education when launching an app pair.

This change ensures that the Taskbar education shows up when a saved app
pair is launched and the education had not been seen before. This
matches the expected behavior as well as transient taskbar's behavior.

Fix: 323298512
Test: Create an app pair, reset taskbar education and launch the app
pair from home. Repeat for 3 button nav and pinned taskbar.
Flag: EXEMPT bugfix

Change-Id: I5ca68424f846f25beb1390c2dc50dfac3ba8e8d9