Fix re-usage of stale cached WebPreferences in RenderViewHost.

Fix re-usage of stale cached WebPreferences in RenderViewHost.

During layout tests when preferences were being overriden they were not
being properly being used as the cached WebPreferences on the
RenderViewHost was not updated. This change fixes that and changes the way
spatial navigation is enabled in layout tests to adapt to this change.

This is an initial change to support the moving of mixed content checks to
the browser.

BUG=576270
Committed: https://crrev.com/db571fbdbd59df71fc8fcb4192adea4c72384801
Cr-Commit-Position: refs/heads/master@{#398276}

[carlosk, 2016-06-06 09:52:12]

carlosk@chromium.org changed reviewers:
+ dpranke@chromium.org, mkwst@chromium.org

[carlosk, 2016-06-06 09:52:13]

mkwst@ and dpranke@: PTAL.

This is an initial change required to later land the moving of mixed content
checks to the browser (WIP in http://crrev.com/1905033002).

The core change is in blink_test_controller.cc where the cached WebPreferences
contents in RenderViewHost are reset when a configuration change is triggered by
layout tests. Otherwise new renderers created would still use the previous,
non-updated WebPreferences.

This made current spatial navigation tests break and that's why the rest of the
changes are needed. They add the spatial navigation flag as a supported test
preference that is then correctly exported to newly created frames.

[Dirk Pranke, 2016-06-06 19:02:12]

lgtm

[Mike West, 2016-06-07 05:36:20]

LGTM, thanks!

[carlosk, 2016-06-07 08:53:36]

The CQ bit was checked by carlosk@chromium.org

[commit-bot: I haz the power, 2016-06-07 08:53:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2042763002/1

[commit-bot: I haz the power, 2016-06-07 12:18:23]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-07 12:19:34]

Description was changed from

==========
Fix re-usage of stale cached WebPreferences in RenderViewHost.

During layout tests when preferences were being overriden they were not
being properly being used as the cached WebPreferences on the
RenderViewHost was not updated. This change fixes that and changes the way
spatial navigation is enabled in layout tests to adapt to this change.

This is an initial change to support the moving of mixed content checks to
the browser.

BUG=576270
==========

to

==========
Fix re-usage of stale cached WebPreferences in RenderViewHost.

During layout tests when preferences were being overriden they were not
being properly being used as the cached WebPreferences on the
RenderViewHost was not updated. This change fixes that and changes the way
spatial navigation is enabled in layout tests to adapt to this change.

This is an initial change to support the moving of mixed content checks to
the browser.

BUG=576270

Committed: https://crrev.com/db571fbdbd59df71fc8fcb4192adea4c72384801
Cr-Commit-Position: refs/heads/master@{#398276}
==========

[commit-bot: I haz the power, 2016-06-07 12:19:35]

Patchset 1 (id:??) landed as
https://crrev.com/db571fbdbd59df71fc8fcb4192adea4c72384801
Cr-Commit-Position: refs/heads/master@{#398276}

[Xianzhu, 2016-06-18 00:01:56]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/2077183002/ by wangxianzhu@chromium.org.

The reason for reverting is: Caused bug 620126. Confirmed by bisecting locally..