RenderObject::frame() should return a reference.
<https://webkit.org/b/120251>

Reviewed by Darin Adler.

There is now always a Frame, and we can get to it by walking this path:

    RenderObject -> Document -> RenderView -> FrameView -> Frame

Removed the customary horde of null checks.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154554 268f45cc-cd09-0410-ab3c-d52691b4dbfc
RetainPtr lacks move constructor for case when argument is a RetainPtr of a different type
https://bugs.webkit.org/show_bug.cgi?id=120255

Reviewed by Andreas Kling.

Source/WTF:

* wtf/RetainPtr.h: Added missing move constructor, modeled on the other move constructor,
and the one from RetPtr.

Tools:

* TestWebKitAPI/Tests/WTF/ns/RetainPtr.mm: Added four tests covering move assignment and construction.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154555 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Merge Document::viewportSize() logic into RenderView::viewportSize().
<https://webkit.org/b/120254>

Reviewed by Darin Adler.

RenderView can just ask FrameView (the viewport) about its size directly, no need for
a weirdly-placed method on Document.

* dom/Document.cpp:
* rendering/RenderView.cpp:
(WebCore::RenderView::viewportSize):
* rendering/RenderView.h:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154556 268f45cc-cd09-0410-ab3c-d52691b4dbfc