Setting icon attribute to null gives error

[jakemac53]

See http://jsbin.com/nusiho/1/edit, click the button and you will see the following error in the console:

Exception caught during observer callback: TypeError: Cannot read property 'split' of null
at core-icon.Polymer.updateAlt (http://www.polymer-project.org/components/core-icon/core-icon.html:188:50)
at core-icon.Polymer.updateIcon (http://www.polymer-project.org/components/core-icon/core-icon.html:147:14)
at core-icon.g.invokeMethod (http://www.polymer-project.org/components/polymer/polymer.js:13:25932)
at core-icon.g.notifyPropertyChanges (http://www.polymer-project.org/components/polymer/polymer.js:13:24037)
at Object.x.report_ (http://www.polymer-project.org/components/polymer/polymer.js:12:18266)
at Object.S.check_ (http://www.polymer-project.org/components/polymer/polymer.js:12:22604)
at c (http://www.polymer-project.org/components/polymer/polymer.js:12:12173)

Original report here dart-archive/core-elements#148

[benjaminapetersen]

Pinging this one, I've been seeing the same thing. It's a bit tricky to nail down if your app has a number of icons as the stack trace doesn't indicate where the problem originates.

[Andersmholmgren]

I'm seeing this a lot too. I'm conditionally setting the icon with an expression for each row in a core-list

[davenotik]

Encountered this too (old Polymer). I simply made sure that I passed an empty string where it otherwise might have been null.