CSSValue Immediates: Replace CSSValue usage with const references

Source/modules/canvas2d/CanvasRenderingContext2DState.h

Index: Source/modules/canvas2d/CanvasRenderingContext2DState.h
diff --git a/Source/modules/canvas2d/CanvasRenderingContext2DState.h b/Source/modules/canvas2d/CanvasRenderingContext2DState.h
index 75401f42c01c9f180642c0f9d6771a57b02e68d6..9d9b5fa8ab4c8823a9eefa2eb2b1f93e36dcf283 100644
--- a/Source/modules/canvas2d/CanvasRenderingContext2DState.h
+++ b/Source/modules/canvas2d/CanvasRenderingContext2DState.h
@@ -80,7 +80,7 @@ public:
     void setUnparsedFont(const String& font) { m_unparsedFont = font; }
     const String& unparsedFont() const { return m_unparsedFont; }
 
-    void setFilter(CSSValue);
+    void setFilter(const CSSValue&);
     void setUnparsedFilter(const String& filterString) { m_unparsedFilter = filterString; }
     const String& unparsedFilter() const { return m_unparsedFilter; }
     SkImageFilter* getFilter(Element*, const Font&) const;