Control Panel not rendered correctly when datasource type is changed

[FrederichCheng]

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• I have checked the superset logs for python stacktraces and included it here as text if any
• I have reproduced the issue with at least the latest released version of superset
• I have checked the issue tracker for the same issue and I haven't found one similar

Superset version

0.18.5

Expected results

Control Panel should be rendered correctly with all the controls related to the target data source when users change the data source from one to another with a different data source type.

Actual results

Some sections have no controls and the following javascript error is shown:'
Uncaught TypeError: Cannot read property 'controlSetRows' of undefined at store.js:16 at Array.forEach (<anonymous>) at getControlNames (store.js:15) at getControlsState (store.js:47) at Object.RESET_FIELDS (exploreReducer.js:158) at exploreReducer (exploreReducer.js:166) at dispatch (createStore.js:165) at index.js:14 at dispatch (applyMiddleware.js:35) at Object.success (exploreActions.js:74)

Steps to reproduce

Change druid type data source to table type data source or vice versa.