Update ContextualSearch check for managed profile.

The previous method returns true for if the user id is either:
 1. In a fully managed device
 2. In work profile

However, we only want to set this flag for #2.

Bug: 377465855
Test: Added tests to ContextualSearchManagerTest
Flag: EXEMPT bugfix
Change-Id: I9a5b6b9bf4b77fd19a673e0041a48ba7b6bb9fd1