This will be needed to handle cases where the client might release its reference to us while
we're calling out to it.

WKCACFLayerRenderer now has a setClient function, which is used rather than passing the
client to create(). This allows clients to null out the client pointer when they're done
with the renderer.

Fixes <http://webkit.org/b/52749> WKCACFLayerRenderer should be
ref-counted

Reviewed by Simon Fraser.

Source/WebCore:

* platform/graphics/win/MediaPlayerPrivateFullscreenWindow.cpp:
(WebCore::MediaPlayerPrivateFullscreenWindow::MediaPlayerPrivateFullscreenWindow):
* platform/graphics/win/MediaPlayerPrivateFullscreenWindow.h:
Updated for WKCACFLayerRenderer changes.

* platform/graphics/win/WKCACFLayerRenderer.cpp:
(WebCore::WKCACFLayerRenderer::acceleratedCompositingAvailable): Updated for changes to
create().
(WebCore::WKCACFLayerRenderer::create): No longer takes a WKCACFLayerRendererClient. Now
returns a PassOwnPtr.
(WebCore::WKCACFLayerRenderer::WKCACFLayerRenderer): No longer takes a
WKCACFLayerRendererClient.

* platform/graphics/win/WKCACFLayerRenderer.h: Made WKCACFLayerRenderer inherit from
RefCounted.
(WebCore::WKCACFLayerRenderer::setClient): Added this simple setter.

Source/WebKit/win:

Update for WKCACFLayerRenderer changes

* WebView.cpp:
(WebView::~WebView): Added some assertions to make sure we've gotten rid of our
compositing-related members. My biggest concern was making sure that m_layerRenderer was
gone, which would also mean we had nulled out its client pointer.
(WebView::setAcceleratedCompositing): Changed to call WKCACFLayerRenderer::setClient instead
of passing the client into create(), and to clear out the client before nulling out
m_layerRenderer.

* WebView.h: Changed m_layerRenderer from an OwnPtr to a RefPtr.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@76256 268f45cc-cd09-0410-ab3c-d52691b4dbfc