WebViewPlugin: Apply Prefs to WebSettings before creating a WebLocalFrame

WebViewPlugin: Apply Prefs to WebSettings before creating WebLocalFrame

If we create a WebLocalFrame and then set blink's settings, the frame
gets an inconsistent view of the settings when they change out from
underneath it.

Concretely, this leads to us doing WebViewImpl::setRootGraphicsLayer(A)
with pinch virtual viewport disabled (the default in WebSettings), when
we attach the document to the tree, then we apply the prefs to enable
pinch virtual viewport, and later setRootGraphicsLayer(NULL) to detach
the document. This causes a crash because the viewport code expects
a matching attach before the detach.

With this CL, https://codereview.chromium.org/261143003 is able to pass
on the print preview and prerender browser tests.

R=bauerb@chromium.org
BUG=376531, 361729
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=272628

[Bernhard Bauer, 2014-05-23 18:59:11]

LGTM! You have a typo in your description though; it took me a while to realize
that "Pres" was supposed to be "prefs".

[danakj, 2014-05-23 18:59:51]

On 2014/05/23 18:59:11, Bernhard Bauer wrote:
> LGTM! You have a typo in your description though; it took me a while to
realize
> that "Pres" was supposed to be "prefs".

Oops thanks :)

[danakj, 2014-05-23 18:59:55]

The CQ bit was checked by danakj@chromium.org

[commit-bot: I haz the power, 2014-05-23 19:01:34]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/danakj@chromium.org/296983017/1

[danakj, 2014-05-23 19:10:26]

+jbroman fyi

[commit-bot: I haz the power, 2014-05-23 22:59:46]

Change committed as 272628