[Mac] Remove unused pageScaleFactor and positionRelativeToBase arguments in GraphicsLayerCA.
https://bugs.webkit.org/show_bug.cgi?id=107357

Patch by Huang Dongsung <luxtella@company100.net> on 2013-01-18
Reviewed by Ryosuke Niwa.

Several methods in GraphicsLayerCA receive a pageScaleFactor or a
positionRelativeToBase argument but don't use the arguments, so this patch
removes them.

No new tests. This is just a refactoring of the existing code.

* platform/graphics/ca/GraphicsLayerCA.cpp:
(WebCore::GraphicsLayerCA::commitLayerChangesBeforeSublayers):
(WebCore::GraphicsLayerCA::updateGeometry):
(WebCore::GraphicsLayerCA::updateStructuralLayer):
(WebCore::GraphicsLayerCA::ensureStructuralLayer):
(WebCore::GraphicsLayerCA::updateLayerDrawsContent):
(WebCore::GraphicsLayerCA::updateContentsScale):
(WebCore::GraphicsLayerCA::swapFromOrToTiledLayer):
* platform/graphics/ca/GraphicsLayerCA.h:
(GraphicsLayerCA):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@140237 268f45cc-cd09-0410-ab3c-d52691b4dbfc