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

Source/core/rendering/RenderTable.cpp

Index: Source/core/rendering/RenderTable.cpp
diff --git a/Source/core/rendering/RenderTable.cpp b/Source/core/rendering/RenderTable.cpp
index b86ee3c8e10e77dd43979c11772206f5245d4994..ab88472d05ff44930884d2081698754713a09c9c 100644
--- a/Source/core/rendering/RenderTable.cpp
+++ b/Source/core/rendering/RenderTable.cpp
@@ -508,7 +508,7 @@ void RenderTable::layout()
     for (RenderTableSection* section = topSection(); section; section = sectionBelow(section))
         section->layoutRows();
 
-    if (!topSection() && computedLogicalHeight > totalSectionLogicalHeight && !document()->inQuirksMode()) {
+    if (!topSection() && computedLogicalHeight > totalSectionLogicalHeight && !document().inQuirksMode()) {
         // Completely empty tables (with no sections or anything) should at least honor specified height
         // in strict mode.
         setLogicalHeight(logicalHeight() + computedLogicalHeight);
@@ -1424,7 +1424,7 @@ RenderTable* RenderTable::createAnonymousWithParentRenderer(const RenderObject*
 {
     RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(parent->style(), TABLE);
     RenderTable* newTable = new RenderTable(0);
-    newTable->setDocumentForAnonymous(parent->document());
+    newTable->setDocumentForAnonymous(&parent->document());
     newTable->setStyle(newStyle.release());
     return newTable;
 }