
This uses @kevmoo's completion package to do command line completion for flutter, and a new command "bash-completion" (with alias "zsh-completion") that will output the necessary shell script setup code, and adds the hidden command "completion" that does the actual completion. Because it adds a dependency, I also had to do flutter update-packages --force-upgrade. Fixes #18988.
microbenchmarks
To run these benchmarks on a device, first run `flutter logs' in one window to see the device logs, then, in a different window, run any of these:
flutter run --release lib/gestures/velocity_tracker_data.dart
flutter run --release lib/stocks/animation_bench.dart
flutter run --release lib/stocks/build_bench.dart
flutter run --release lib/stocks/layout_bench.dart
The results should be in the device logs.