Description

The integration tests can be configured to use a specific local engine
variant by setting the FLUTTER_LOCAL_ENGINE environment variable to the
name of the local engine (e.g. "android_debug_unopt"). If the local engine build
requires a source path, this can be provided by setting the FLUTTER_LOCAL_ENGINE_SRC_PATH
environment variable. This second variable is not necessary if the flutter and
engine checkouts are in adjacent directories.

export FLUTTER_LOCAL_ENGINE=android_debug_unopt
../../bin/dart test test/integration.shard/some_test_case

Fixes #65106