| ⇢ | A | FileTypeCreatorTest added |
| ⇢ | B | FileTypeCreator::getThumbnail() added | |
| ⇢ | A | FileTypeCreatorTest::testThumbnail() added | |
| ⇢ | A | FileTypeCreatorTest::setUp() added | |
| ⇢ | A | FileTypeCreatorTest::tearDown() added | |
| A | ↘ | B | FileTypeCreator::resolveThumbnailField() got worse |