Enterprise Vault OWA Extensions in 10.0.4 CHF2

Hello.  I am in the process of upgrading Enterprise Vault from v10.0.3 to v10.0.4 with Cumulative Hotfix 2.

We are performing this upgrade for compatibility with Exchange 2013 SP1.

I noticed that while Enterprise Vault OWA Extensions are not required for Exchange 2013, a "Enterprise Vault OWA Extensions" package for 2010 is included in the Cumulative Hotfix.

What functionality does this correct/provide?  If we are ultimately migrating users from Exchange 2010 to Exchange 2013, do I need to install them?  I would like to avoid modifying our Exchange 2010 servers if possible.

Thanks.