## Bug description

Trying to look at insights for feature flags no longer works (see screenshot below).

<img width="1329" alt="" src="https://user-images.githubusercontent.com/5864173/100642031-de24cb00-32fd-11eb-88b4-047c4f82124f.png">


Removing the breakdown works but then you can't see the difference between the binary values.

![image](https://user-images.githubusercontent.com/5864173/100642046-e2e97f00-32fd-11eb-8ae5-4238f899c8b8.png)


## Expected behavior

Insights should be shown as before.


## How to reproduce

1. Click on the insights link on any feature flag row.

## Environment

Cloud (Clickhouse).

## Additional context



#### *Thank you* for your bug report – we love squashing them!

ee/clickhouse/queries/trends/breakdown.py
self,
        index: int,
        breakdown_type: Optional[str],
        breakdown: Union[str, List[Union[str, int]], None],
        value: Union[str, int],
    ) -> str:
        breakdown = breakdown if breakdown and isinstance(breakdown, list) else []
        if breakdown_type == "cohort":
            if breakdown[index] == "all":
                return "all users"
            else:
                return Cohort.objects.get(pk=breakdown[index]).name
        else:
            return str(value) or ""
    def _get_top_elements(self, query: str, filter: Filter, team_id: int) -> List: