* add trailing commas on list/map/parameters
* add trailing commas on Invocation with nb of arg>1
* add commas for widget containing widgets
* add trailing commas if instantiation contains trailing comma
* revert bad change
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.
