Fixes: #111008

Scenario

• The current editor scale is 100%.
• A new resource is created, flagged as scale with editor scale and reimported.
  • File .godot/imported/[resource].editor.meta is created.
• The user change editor scale to 200% and restarts editor.
• The imported editor resource how still original scale, because reimport was not applied.
  • Timestamp of resource (or its .import file) is still the same, so _is_test_for_reimport_needed returns false.

Note: Same goes for convert colors with editor theme.

Proposal

• A new file .godot/imported/.editor.meta is introduced.

  • This file contains editor scale of the last import of editor resources.

• The file is loaded during EditorFileSystem::_scan_filesystem call and used to determine if editor requests different scale.

  • This allows to keep timestamp optimization and flag only editor resources for testing for reimport if needed.

• Bugsquad edit: supersedes Fix editor resources importing #111009