Deflake NavigateTest.testWindowOpenUrlSpoof

Deflake NavigateTest.testWindowOpenUrlSpoof

* Change it so that you can click on the entire body instead of a link,
  which is flaky because the DOMUtils doesn't know where the link is
  occasionally.

* Supplement the URL check with a viewport check to see that the page
  has loaded before checking the URL.

BUG=413186
Committed: https://crrev.com/6009f41b7b062b84426cc508f5c3719451ab7afd
Cr-Commit-Position: refs/heads/master@{#333400}

[gone, 2015-06-09 00:15:39]

dfalcantara@chromium.org changed reviewers:
+ dtrainor@chromium.org, tedchoc@chromium.org

[gone, 2015-06-09 00:15:40]

Tries to deflake the last NavigateTest.  Haven't had it fail locally after
multiple runs, but who knows how the downstream bots'll treat it.

[David Trainor- moved to gerrit, 2015-06-09 00:17:28]

lgtm

[gone, 2015-06-09 00:18:15]

The CQ bit was checked by dfalcantara@chromium.org

[gone, 2015-06-09 00:18:17]

The CQ bit was checked by dfalcantara@chromium.org

[commit-bot: I haz the power, 2015-06-09 00:18:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1172503002/1

[commit-bot: I haz the power, 2015-06-09 00:36:56]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-09 00:37:57]

Patchset 1 (id:??) landed as
https://crrev.com/6009f41b7b062b84426cc508f5c3719451ab7afd
Cr-Commit-Position: refs/heads/master@{#333400}