Integrate API into App-to-Web

Applications can now provide another web uri using
AssistContent#EXTRA_TRANSFER_SESSION_TRANSFER_WEB_URI which should be
prioratized when a user switches to the browser. This change does the
following:
1. Gets and uses the new API's uri if available
2. Fixes the ordering of the URIs to match latest spec

Bug: 349695493
Test: Use open in browser button in header menu after clicking on link
Flag: com.android.window.flags.enable_desktop_windowing_app_to_web
Change-Id: Id56a5b1c99d9f2ffadb1e95dfbad09fdba38e7ee