anchor.diff:  
       // there is a small chance that the process is interrupted before this gets
       // deleted, but the [removeObsolete] should be able to validate it.
  -    await _storage.delete(entry.inProgressObjectName);
  +    await _deleteFile(entry.inProgressObjectName);
   
       await dartdocMemcache?.invalidate(entry.packageName, entry.packageVersion);
     }
  
positive.code:       for (var item in page.items) {
          count++;
          final pooledDelete =
              deletePool.withResource(() => _storage.delete(item.name));
          deleteFutures.add(pooledDelete);
        }
        await Future.wait(deleteFutures);
  
negative.code:         final info = await _storage.info(entry.name);
          final age = new DateTime.now().difference(info.updated);
          if (age > _sdkDeleteThreshold) {
            await _deleteFile(entry.name);
          }
        }
      }
  