Log Viewer doesn't respect log entry severity when logging from cloud functions

The log viewer ignores the severity of log entries. When logging errors from cloud functions running in the emulator the entries always display with a severity of 'Info'. I tried using the standard `console.error()` and `functions.logger.error()`. I also tried logging with and without Error objects:

```typescript
functions.logger.error('Error 1')
functions.logger.error(new Error('Error 2'))
console.error('Error 3')
console.error(new Error('Error 4'))
```

All display in the Log Viewer with a severity of 'Info' in the gutter: