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

Source/core/rendering/RootInlineBox.cpp

Index: Source/core/rendering/RootInlineBox.cpp
diff --git a/Source/core/rendering/RootInlineBox.cpp b/Source/core/rendering/RootInlineBox.cpp
index 9a3da5d67417bf6eeb393493019f753b9b44594a..860da2498e8458de87006907fab8b7d6fec44306 100644
--- a/Source/core/rendering/RootInlineBox.cpp
+++ b/Source/core/rendering/RootInlineBox.cpp
@@ -250,7 +250,7 @@ LayoutUnit RootInlineBox::alignBoxesInBlockDirection(LayoutUnit heightOfBlock, G
     bool setMaxDescent = false;
 
     // Figure out if we're in no-quirks mode.
-    bool noQuirksMode = renderer()->document()->inNoQuirksMode();
+    bool noQuirksMode = renderer()->document().inNoQuirksMode();
 
     m_baselineType = requiresIdeographicBaseline(textBoxDataMap) ? IdeographicBaseline : AlphabeticBaseline;
 
@@ -842,7 +842,7 @@ LayoutUnit RootInlineBox::verticalPositionForBox(InlineBox* box, VerticalPositio
 
     // This method determines the vertical position for inline elements.
     bool firstLine = isFirstLineStyle();
-    if (firstLine && !renderer->document()->styleSheetCollections()->usesFirstLineRules())
+    if (firstLine && !renderer->document().styleSheetCollections()->usesFirstLineRules())
         firstLine = false;
 
     // Check the cache.