Move content preview outside of the ViewPager (work tab part 2)

This is needed so that we show the content preview independently
from the tabs.

Test: manually performed text and picture sharing on a 1-user device
Test: manually performed text and picture sharing on a device with
work profile on both profiles
Test: atest com.android.internal.app.ResolverActivityTest
Test: atest com.android.internal.app.ChooserActivityTest
Test: atest com.android.internal.app.ResolverListControllerTest
Bug: 142537267
Bug: 142538125

Change-Id: Ib7d8b704007643f46765fbf8abfe97bb814604cd