Add use counters for the passive option to addEventListener

We've long tracked the primary metric - how often do scrolls block
unnecessarily (via the Event.PassiveListeners histogram) but the results
are complex.  To help interpret the results let's also just count
how common it is for a page to use the 'passive' option anywhere.
This isn't directly meaningful by itself in terms of outcomes, but
is still useful as a rough indication of developer adoption for the API.

BUG=489802
TBR=rkaplow

Review-Url: https://codereview.chromium.org/2090903003
Cr-Commit-Position: refs/heads/master@{#401703}
3 files changed