private JsonField<AgentNameView, List<TimeHistogramViewModel>> createAgentResponseTimeViewModel(Application agentName, List<TimeHistogram> timeHistogramList, TimeHistogramFormat timeHistogramFormat) {
        List<TimeHistogramViewModel> responseTimeViewModel = createResponseTimeViewModel(timeHistogramList, timeHistogramFormat);
        return JsonField.of(AgentNameView.of(agentName), responseTimeViewModel);
    }
most of the features have been delegated to AgentHistogramList upon refactoring
TODO: functionality reduced to creating views - need to be renamed or removed

@author emeroad
web/src/main/java/com/navercorp/pinpoint/web/applicationmap/histogram/AgentTimeHistogram.java