Filing this to investigate why some of the assets we use as icon images are missing during macos golden testing.

The changes in https://github.com/flutter/devtools/pull/9304/files caused some icons that weren't being rendered previously in our macos golden tests to appear, as well as others that were being rendered in our macos golden tests to disappear.

The assets that were previously missing are:

• packages/devtools_app/icons/material_symbols/step_over.png
• packages/devtools_app/icons/material_symbols/step_into.png
• packages/devtools_app/icons/material_symbols/step_out.png

The asset that is now missing is:

• packages/devtools_app/icons/flutter.png

All 4 of the assets display as expected in a running app, and all 4 are included in the pubspec:

• devtools/packages/devtools_app/pubspec.yaml

  Line 96 in 8e65592

  - icons/

• devtools/packages/devtools_app/pubspec.yaml

  Line 100 in 8e65592

  - icons/material_symbols/

packages/devtools_app/test/test_infra/goldens/codeview_scrollbars.png:

Note: The code for these buttons was not touched in #9304:

packages/devtools_app/test/test_infra/goldens/logging/metadata_chips.png

Note: The code for these icons also didn't change, except for the icon size becoming const: