Rework Android Emulators and such

# Install required stuff

## Android Tools

```
brew install --cask android-platform-tools
brew install --cask android-studio
```

### Questions / 2check

- Android Studio really needed?
- What about former `android-ndk` and `android-sdk` that were installed?
- And what about `java8` which me might need for building?
- On https://dev.to/0xdonut/how-to-install-flutter-on-macos-using-homebrew-and-asdf-3loa I read:
```
brew install android-sdk
brew install android-studio
brew install haxm
brew install --cask adoptopenjdk8
```

## Specific SDKs

```
sdkmanager "platform-tools" "extras;intel;Hardware_Accelerated_Execution_Manager" "emulator"
```

_(Questions: Long ago I also installed `"platforms;android-25" "build-tools;25.0.3"` which is needed for building. I see that `"build-tools;28.0.3"` is still installed on my system too …)_

# Create Android Emulators

_@ref https://gist.github.com/mrk-han/66ac1a724456cadf1c93f4218c6060ae_

## (Android 9, Chrome 69)

```
sdkmanager --install "system-images;android-28;google_apis;x86"
echo "no" | avdmanager --verbose create avd --force --name "pixel_9.0" --device "pixel" --package "system-images;android-28;google_apis;x86" --tag "google_apis" --abi "x86"
alias pixel_9.0='emulator @pixel_9.0 -no-boot-anim -netdelay none -no-snapshot -skin 1080x1920'
```

## (Android 10, Chrome 74)

```
sdkmanager --install "system-images;android-29;google_apis;x86"
echo "no" | avdmanager --verbose create avd --force --name "pixel_10.0" --device "pixel" --package "system-images;android-29;google_apis;x86" --tag "google_apis" --abi "x86"
alias pixel_10.0='emulator @pixel_10.0 -no-boot-anim -netdelay none -no-snapshot -skin 1080x1920'
```

## (Android 11, Chrome 83)

```
sdkmanager --install "system-images;android-30;google_apis;x86"
echo "no" | avdmanager --verbose create avd --force --name "pixel_11.0" --device "pixel" --package "system-images;android-30;google_apis;x86" --tag "google_apis" --abi "x86"
alias pixel_11.0='emulator @pixel_11.0 -no-boot-anim -netdelay none -no-snapshot -skin 1080x1920'
```

# Connect Hardware Keyboard to Emulators

_@ref https://coderwall.com/p/i2heaw/enable-hardware-keyboard-input-in-android-emulators_

Edit all avd configs and add `hw.keyboard=yes` to them.

One-liner:

```
for f in ~/.android/avd/*.avd/config.ini; do echo 'hw.keyboard=yes' >> "$f"; done
```