* Use `curly_braces_in_flow_control_structures` for `packages/flutter_driver`

* Use `curly_braces_in_flow_control_structures` for `packages/flutter_goldens`

* Use `curly_braces_in_flow_control_structures` for `packages/flutter_goldens_client`

* Use `curly_braces_in_flow_control_structures` for `packages/flutter_localizations`

* Use `curly_braces_in_flow_control_structures` for `packages/flutter_test`

* Use `curly_braces_in_flow_control_structures` for `packages/flutter_web_plugins`

* fix comments

* Use `curly_braces_in_flow_control_structures` for `packages/integration_test`

* fix indentation

* Update material_id.arb

* Update README.md

* Update generated_material_localizations.dart

* Update README.md

* remove trailing whitespace

When I added localizations for shortcut keys, I added some that actually can't be shortcut keys, so I'm removing them again. These are mostly Japanese-specific keys that don't even appear on modern keyboards for the most part.

Also, added menuBarMenuLabel for an accessibility label for menu bar menus.

I modified the code for the localization generation scripts to add a --remove-undefined flag that will remove any localizations that don't appear in the canonical locale.

This change adds some localizations for keyboard keys that will be used in creating shortcut descriptions in menus.

Co-authored-by: Shi Hao Hong <shihaohong94@gmail.com>

Migrate flutter_localizations to null safety.

This reverts commit ae06c19a.

* Expose date symbols and patterns for en_US in framework

* Regenerate _no.arb and _nb.arb from scratch

* Revert no <--> nb synonym logic

* Normalize Pashto incomplete translations

* Add comment to README.md about incomplete Pashto support