fix: on-change event in shadowRoot

[alimd]

As you know, In the Shadow DOM, the change event is not leaked into the ancestor tree, so we must do this manually.
This is done in the rest of the input components by paper-input-behavior.

Fixed PolymerElements/paper-input#664

[alimd]

@notwaldorf We have an issue in our app and need to fix it as soon as possible
Could you please review/merge this PR with priority
Thank you in advance.

[alimd]

travis error is not related to this PR changes!

[notwaldorf]

The travis error is actually related to this PR: it says `Typings are stale. Please run "npm run update-types". You've added a new event type, which needs to be typed :)

Please update the types, then this should be good to merge

[notwaldorf]

(you need to update the typings)

[alimd]

@notwaldorf
Oops!
Excuse me.

[alimd]

Why issue remains?!

[alimd]

@notwaldorf
I fix the generated declaration manually, but could you please check this issue for future PR?

My generated declaration
interface IronAutogrowTextareaElement extends Polymer.IronValidatableBehavior, Polymer.IronControlState, Polymer.LegacyElementMixin, HTMLElement {

Travise
interface IronAutogrowTextareaElement extends Polymer.Element, Polymer.IronValidatableBehavior, Polymer.IronControlState {

https://travis-ci.org/PolymerElements/iron-autogrow-textarea/builds/413055027?utm_source=github_status&utm_medium=notification

[notwaldorf]

cc @bicknellr for a release