Add testRunner.dumpNavigationPolicy() to be able to the the navigation policy

Add testRunner.dumpNavigationPolicy() to be able to the the navigation policy

Since content_shell doesn't support tabs, we can't otherwise tell apart
background tabs from foreground tabs in layout tests.

BUG=454222
R=mkwst@chromium.org,rbyers@chromium.org

Committed: https://crrev.com/c3a98da19b1c732ae1313f1c8f6c17186be604fa
Cr-Commit-Position: refs/heads/master@{#319873}

[jochen (gone - plz use gerrit), 2015-03-10 12:56:13]

ptal

[Mike West, 2015-03-10 13:09:22]

LGTM.

[Mike West, 2015-03-10 13:10:35]

https://codereview.chromium.org/995773002/diff/1/content/shell/renderer/test_...
File content/shell/renderer/test_runner/web_test_proxy.cc (right):

https://codereview.chromium.org/995773002/diff/1/content/shell/renderer/test_...
content/shell/renderer/test_runner/web_test_proxy.cc:1326:
URLDescription(info.urlRequest.url()) + " is '" +
Nit: If you put quotes around the URL, it'll stand out more in the console
message.

[jochen (gone - plz use gerrit), 2015-03-10 13:18:44]

The CQ bit was checked by jochen@chromium.org

[jochen (gone - plz use gerrit), 2015-03-10 13:18:44]

The patchset sent to the CQ was uploaded after l-g-t-m from mkwst@chromium.org
Link to the patchset: https://codereview.chromium.org/995773002/#ps20001 (title:
"updates")

[commit-bot: I haz the power, 2015-03-10 13:18:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/995773002/20001

[commit-bot: I haz the power, 2015-03-10 14:00:09]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-10 14:00:48]

Patchset 2 (id:??) landed as
https://crrev.com/c3a98da19b1c732ae1313f1c8f6c17186be604fa
Cr-Commit-Position: refs/heads/master@{#319873}