Enabling Project Feature fails and crashes app, requiring browser refresh

[Colinh84]

In Project specification under the add/edit features section, if you select any menu option from the left menu, click the enable toggle, and fill in the Notes.. input too quickly, then click another option from the left menu, it gives a JS error in console and all links/buttons in the app become inoperable, requiring a browser refresh to resume.

Expected behavior

Enabling a feature and adding to the Notes.. section should not crash the app.

Actual behavior

Working too quickly enabling a feature crashes the app

Steps to reproduce the problem

• Create a new project.
• navigate to connectv2.topcoder-dev.com/projects/{xxx}/specification page for project
• Scroll to "feature requirements" section and click "Add/Edit Features" button.
• Click any menu item from the left.
• Click the top-right slider to enable feature.
• Edit the Notes.. input with a few words of text, then click on another option from the menu on the left. (Do this fairly quickly, taking up to a few seconds)
• When other menu item is selected, the checkmark next to the feature you just left disappears, and all links and buttons are now inoperable.
• There is an error in the console:

FlattenedFeatureList.jsx:32 Uncaught TypeError: Cannot read property 'categoryId' of undefined

Screenshot/screencast

http://i.imgur.com/BRnr5Qj.png

Environment

• OS: Win10
• Browser (w/version): Chrome 53
• User role (client, copilot or manager): client
• Account used: christina_uw

[mahestro]

Valid.

[vikasrohit]

@parthshah this one is happening because of debounced onChange handler. It gets fired after the user has changed the active feature from the left menu. And it happens when user closes the feature picker immediately after changing the notes. But in this case error in console is different:
Warning: setState(...): Can only update a mounted or mounting component. This usually means you called setState() on an unmounted component. This is a no-op. Please check the code for the FeaturePicker component.

[vikasrohit]

@parthshah I have committed a fix(which I have used for the custom feature) for the problem in branch named standard-feature-picker-fixes. Please merge it into dev, if you find it suitable as fix.

[parthshah]

@vikasrohit re-assigning this to you. Please close once the fix is in dev.