Adds a Fuchsia compatibility function that allows for connecting to a
specific Isolate by name when running Flutter Driver on a Fuchsia
device. This will check over multiple Dart VM's in an attempt to find
an Isolate by its name.
The test places an embedded Android view at the top left, and verifies
that motion events that get to FlutterView are equivalent to the
synthesized motion events that gets to the embedded view.
See the README.md for more high level details.