None of the components should directly interact with the proxy because
non-android development workflow (using web adb) will also be possible
in the future. Instead the ui components interact with a common
connection interface which handles the proxy or web adb respectively.
Test: check that proxy workflow still works as expected.
Bug: b/234103636
Change-Id: I0e7bbaf4b5f342ca99dd67f890c135dbf3ef61ec