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This cl adds use counters to find out the ratio of the web pages that
add document level wheel event listeners with passive:false, true, or
unspecified. It also counts the number of document level wheel event
listeners with passive:unspecified that preventDefault wheel events.

This information is useful to investigate the potential performance
benefits and risks of changing the default value of the passive option
to be true for document level wheel/mousewheel event listeners.

Bug: 626196
Change-Id: Ib0ee64b1a5085813d9b70073747ec3f544fbb660
Reviewed-on: https://chromium-review.googlesource.com/1148783
Commit-Queue: Sahel Sharify <sahel@chromium.org>
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Cr-Commit-Position: refs/heads/master@{#578695}