Have Node::document() return a reference instead of a pointer

Source/core/rendering/FlowThreadController.cpp

Index: Source/core/rendering/FlowThreadController.cpp
diff --git a/Source/core/rendering/FlowThreadController.cpp b/Source/core/rendering/FlowThreadController.cpp
index c061075b6369cfcbd39f9f824e4b9113ba1686a1..d7f05596c76978400ef54da463e3096800c5808c 100644
--- a/Source/core/rendering/FlowThreadController.cpp
+++ b/Source/core/rendering/FlowThreadController.cpp
@@ -67,12 +67,12 @@ RenderNamedFlowThread* FlowThreadController::ensureRenderFlowThreadWithName(cons
         }
     }
 
-    NamedFlowCollection* namedFlows = m_view->document()->namedFlows();
+    NamedFlowCollection* namedFlows = m_view->document().namedFlows();
 
     // Sanity check for the absence of a named flow in the "CREATED" state with the same name.
     ASSERT(!namedFlows->flowByName(name));
 
-    RenderNamedFlowThread* flowRenderer = RenderNamedFlowThread::createAnonymous(m_view->document(), namedFlows->ensureFlowWithName(name));
+    RenderNamedFlowThread* flowRenderer = RenderNamedFlowThread::createAnonymous(&m_view->document(), namedFlows->ensureFlowWithName(name));
     flowRenderer->setStyle(RenderFlowThread::createFlowThreadStyle(m_view->style()));
     m_renderNamedFlowThreadList->add(flowRenderer);