https://bugs.webkit.org/show_bug.cgi?id=92794

Patch by Alexandre Elias <aelias@google.com> on 2012-08-02
Reviewed by Adrienne Walker.

In the future, CSS layout size will become increasingly disassociated
from physical device size, and it will become impossible to infer one
from the other inside the compositor.  Therefore, this patch allows
deviceViewportSize to be explicitly passed in by the outside client.

I also renamed the existing viewportSize field to "layoutViewportSize"
for clarity, and converted its uses to deviceViewportSize since
that is more appropriate.

I had to add some default-value scaffolding to WebLayerTreeView in
order to avoid breaking ui/compositor.  We can delete it once that's
updated.

Source/Platform:

* chromium/public/WebLayerTreeView.h:
(WebLayerTreeView):

Source/WebCore:

No new tests (covered by existing tests).

* platform/graphics/chromium/cc/CCLayerTreeHost.cpp:
(WebCore::CCLayerTreeHost::finishCommitOnImplThread):
(WebCore::CCLayerTreeHost::setViewportSize):
(WebCore::CCLayerTreeHost::updateLayers):
(WebCore::CCLayerTreeHost::setDeviceScaleFactor):
* platform/graphics/chromium/cc/CCLayerTreeHost.h:
(CCLayerTreeHost):
(WebCore::CCLayerTreeHost::layoutViewportSize):
* platform/graphics/chromium/cc/CCLayerTreeHostImpl.cpp:
(WebCore::CCLayerTreeHostImpl::canDraw):
(WebCore::CCLayerTreeHostImpl::startPageScaleAnimation):
(WebCore::CCLayerTreeHostImpl::setViewportSize):
(WebCore::CCLayerTreeHostImpl::setDeviceScaleFactor):
(WebCore::CCLayerTreeHostImpl::updateMaxScrollPosition):
* platform/graphics/chromium/cc/CCLayerTreeHostImpl.h:
(CCLayerTreeHostImpl):
(WebCore::CCLayerTreeHostImpl::layoutViewportSize):

Source/WebKit/chromium:

* src/WebLayerTreeView.cpp:
(WebKit::WebLayerTreeView::setViewportSize):
(WebKit::WebLayerTreeView::layoutViewportSize):
(WebKit):
(WebKit::WebLayerTreeView::deviceViewportSize):
(WebKit::WebLayerTreeView::setDeviceScaleFactor):
* src/WebViewImpl.cpp:
(WebKit::WebViewImpl::paint):
(WebKit::WebViewImpl::updateLayerTreeViewport):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@124543 268f45cc-cd09-0410-ab3c-d52691b4dbfc