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

Source/core/css/PropertySetCSSStyleDeclaration.cpp

Index: Source/core/css/PropertySetCSSStyleDeclaration.cpp
diff --git a/Source/core/css/PropertySetCSSStyleDeclaration.cpp b/Source/core/css/PropertySetCSSStyleDeclaration.cpp
index aa7c9ee14ec620fb5028d9525ceec05a8f2c007c..64107b40882cbba1ee3cda0f2391ac6e474f9e0f 100644
--- a/Source/core/css/PropertySetCSSStyleDeclaration.cpp
+++ b/Source/core/css/PropertySetCSSStyleDeclaration.cpp
@@ -91,8 +91,8 @@ public:
         PropertySetCSSStyleDeclaration* localCopyStyleDecl = s_currentDecl;
         s_currentDecl = 0;
         s_shouldNotifyInspector = false;
-        if (localCopyStyleDecl->parentElement() && localCopyStyleDecl->parentElement()->document())
-            InspectorInstrumentation::didInvalidateStyleAttr(localCopyStyleDecl->parentElement()->document(), localCopyStyleDecl->parentElement());
+        if (localCopyStyleDecl->parentElement())
+            InspectorInstrumentation::didInvalidateStyleAttr(&localCopyStyleDecl->parentElement()->document(), localCopyStyleDecl->parentElement());
     }
 
     void enqueueMutationRecord()
@@ -418,7 +418,7 @@ void InlineCSSStyleDeclaration::didMutate(MutationType type)
 
 CSSStyleSheet* InlineCSSStyleDeclaration::parentStyleSheet() const
 {
-    return m_parentElement ? m_parentElement->document()->elementSheet() : 0;
+    return m_parentElement ? m_parentElement->document().elementSheet() : 0;
 }
 
 } // namespace WebCore