Replace RenderArena with PartitionAlloc.

Source/core/rendering/RenderView.cpp

Index: Source/core/rendering/RenderView.cpp
diff --git a/Source/core/rendering/RenderView.cpp b/Source/core/rendering/RenderView.cpp
index 32d63a0bcfa7130e5b007de7b28550cd4e6f33e5..d484b2ada8974ec37fd4fa50fac626eee10a077f 100644
--- a/Source/core/rendering/RenderView.cpp
+++ b/Source/core/rendering/RenderView.cpp
@@ -870,7 +870,7 @@ void RenderView::releaseWidgets(Vector<RenderWidget*>& renderWidgets)
     size_t size = renderWidgets.size();
 
     for (size_t i = 0; i < size; ++i)
-        renderWidgets[i]->deref(renderArena());
+        renderWidgets[i]->deref();
 }
 
 void RenderView::updateWidgetPositions()
@@ -992,7 +992,7 @@ void RenderView::pushLayoutState(RenderObject* root)
     ASSERT(m_layoutStateDisableCount == 0);
     ASSERT(m_layoutState == 0);
 
-    m_layoutState = new (renderArena()) LayoutState(root);
+    m_layoutState = new LayoutState(root);
 }
 
 bool RenderView::shouldDisableLayoutStateForSubtree(RenderObject* renderer) const