Make sure you have updated to the latest Flutter master.
Check what version of Chrome is running on the machine you're running tests on.
Download and install driver for that version from here:
Start the driver using chromedriver --port=4444
Change into the test
directory of your clone.
Run tests: flutter drive -d web-server --browser-name=chrome --target=test_driver/TEST_NAME_integration.dart
, or (in Linux):
./run_test test_driver/TEST_NAME_integration.dart
./run_test