Changing Visualization after removing all metrics throws an unhandled error

[mtgraham]

Describe the bug When changing visualizations, the new visualization model is created. If there are no metrics in the request, the visualization creation will throw an uncaught error.

To Reproduce Steps to reproduce the behavior:

1. Go to https://yahoo.github.io/navi/#/reports/1/view
2. Remove all metrics
3. Select the Bar Chart visualization
4. See error in console

Expected behavior Error should be handled in some way such as rendering a table with only dimension columns or giving a warning message and aborting the visualization change.

Screenshots If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: MacOS
• Browser Chrome
• Version 79.0.3945.117

[jkusa]

Need to check if still issue an issue