Implement new API

This is the first swack at the new, 2-phase API. Adds the new methods
to the resolver service and makes the split name explicit on the
installer intent.

The 2nd phase will not yet be invoked; that's coming in a follow-on
change.

Bug: 25119046
Test: build & install the sample resolver and run 'adb shell am start -a android.intent.action.VIEW -c android.intent.category.BROWSABLE -d "https://www.tripadvisor.com/Tourism-g33020-San_Jose_California-Vacations.html"'
Change-Id: I2df6fa64d46f17a86a2e32b19417632c594fb10f