Make InlineBox::renderer() and related subclass methods return reference.

Source/core/rendering/svg/RenderSVGInline.cpp

Index: Source/core/rendering/svg/RenderSVGInline.cpp
diff --git a/Source/core/rendering/svg/RenderSVGInline.cpp b/Source/core/rendering/svg/RenderSVGInline.cpp
index 64f6b4d66accd8193cc09e9e46557f9f35ff74c9..b813b27d76ce4b23bd67343edf1add81db5ee774 100644
--- a/Source/core/rendering/svg/RenderSVGInline.cpp
+++ b/Source/core/rendering/svg/RenderSVGInline.cpp
@@ -56,7 +56,7 @@ RenderSVGInline::RenderSVGInline(Element* element)
 
 InlineFlowBox* RenderSVGInline::createInlineFlowBox()
 {
-    InlineFlowBox* box = new SVGInlineFlowBox(this);
+    InlineFlowBox* box = new SVGInlineFlowBox(*this);
     box->setHasVirtualLogicalHeight();
     return box;
 }