Enable PassiveDocumentEventListeners feature

We decide to ship the intervention of 'Uncancelable Touch Events During A Fling',
so enable 'PassiveDocumentEventListeners' feature.

Below is the link to the discussion on blink-dev
https://groups.google.com/a/chromium.org/d/topic/blink-dev/wJGmsdYxwrg/discussion

BUG=595327

Review-Url: https://codereview.chromium.org/2556723006
Cr-Commit-Position: refs/heads/master@{#437544}
1 file changed