[a11y] loading indicator should have correct semantics role #161631
Description
When using https://api.flutter.dev/flutter/material/CircularProgressIndicator-class.html, the loading spinner should have following role
| OS | role |
|---|---|
| web | - |
| ios | - |
| macos | NSAccessibilityProgressIndicatorRole |
| windows | - |
| android | - |
When using https://api.flutter.dev/flutter/material/LinearProgressIndicator-class.html, the linear indicator should have following role
| OS | role |
|---|---|
| web | progressbar |
| ios | - |
| macos | NSAccessibilityLevelIndicatorRole |
| windows | ROLE_SYSTEM_PROGRESSBAR |
| android | - |