Performance problem with many elements in the page

[felixzapata]

Description

The iron-autogrow-textarea element causes the page to have a low performance in a scenario with many components in the same page.

When you type on the input, there is a big delay for the user.

Expected outcome

No delay when the user is typing on the input.

Actual outcome

There is a big delay for the user and if you get a profile from the performance tab.

Live Demo

Steps to reproduce

Browsers Affected

Only tested with Crome:

• [x] Chrome
• [ ] Firefox
• [ ] Safari 9
• [ ] Safari 8
• [ ] Safari 7
• [ ] Edge
• [ ] IE 11
• [ ] IE 10