can't scroll in the embedded demo page of iron-collapse (ios 10.1.1)

[valdrinkoshi]

Description

can't scroll in the embedded demo page of iron-collapse after expanding the content.

Expected outcome

You can scroll to see all content.

Actual outcome

No Scrolling possible

Live Demo

https://elements.polymer-project.org/elements/iron-collapse?view=demo:demo/index.html&active=iron-collapse

Steps to reproduce

1. Use an iPhone
2. Go to the demo page of the iron-collapse. The content must not use all of the screen (use link above)
3. Toggle the iron-collapse the get all the content. The content must use all of the screen
4. Try to scroll

Browsers Affected

• Chrome
• Firefox
• Safari for iOS
• Safari 9
• Safari 8
• Safari 7
• Edge
• IE 11
• IE 10