>>>
when(mockLoader.loadData(expectedRequestMetricInitialDateCTR))
    .thenReturn(
         _buildMinimalResponseFuture(MetricType.CTR, metricRequest));
<<<
### TODO(rnystrom): I think it would look better to split the method chain.
when(
  mockLoader.loadData(expectedRequestMetricInitialDateCTR),
).thenReturn(_buildMinimalResponseFuture(MetricType.CTR, metricRequest));