This reverts commit 2ca250d409adfa73a666daabd3ba19b94d6443a7.

Reason for revert: A leak bot complains navigation-consumes-user-activation.tentative.sub.html is leaking.
Sample build:
https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linux%20Trusty%20Leak/builds/17509

Original change's description:
> Enable ConsumeGestureOnNavigation by default
>
> See blink-dev thread:
> https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/kPli8ZCUeok
>
> A browser test is moved to be a tentative WPT due to this change.
>
> Bug: 772515
> Change-Id: Icf99c8c303c5055dcbcdace6ae94e3fcd1a01921
> Reviewed-on: https://chromium-review.googlesource.com/980599
> Reviewed-by: Nasko Oskov <nasko@chromium.org>
> Reviewed-by: Mustaq Ahmed <mustaq@chromium.org>
> Reviewed-by: Jonathon Kereliuk <kereliuk@chromium.org>
> Commit-Queue: Charlie Harrison <csharrison@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#549293}

TBR=nasko@chromium.org,mustaq@chromium.org,csharrison@chromium.org,kereliuk@chromium.org

Change-Id: I0c998798d1367be61c633db76429c18ac554e4ff
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 772515
Reviewed-on: https://chromium-review.googlesource.com/1003437
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Commit-Queue: Makoto Shimazu <shimazu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549363}