paper-button throws violation warning message

[yveslange]

Description

The paper-button element throws a warning in the console:

gestures.html:435 [Violation] Added non-passive event listener to a scroll-blocking 'touchstart' event. Consider marking event handler as 'passive' to make the page more responsive. See https://www.chromestatus.com/feature/5745543795965952

Expected outcome

It should not throw this warning

Live Demo

https://www.webcomponents.org/element/PolymerElements/paper-icon-button

Steps to reproduce

Import and use the paper-button or paper-icon-button

Browsers Affected

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

[keanulee]

Consider using Polymer.setPassiveTouchGestures(true) to fix this. We can't do this at the element level though, since some apps may use gestureEvent.preventDefault() to prevent scrolling. For more details, see https://github.com/Polymer/polymer/releases/tag/v2.1.0