Move ContactInfo request classes to package.

Once a ContactInfoCache is implemented, these will be changed to have
package visibility. This is an incremental step of breaking out and
moving these classes to a "contactinfo" package. The next CL will
actually implement the Cache and have more churn in terms of logic,
while this is more straightforward.

Bug: 20038300
Change-Id: Ie6082b2eeab52e25f861f2459517fff057370f82