Update Element API for CSSOM smooth scrolling to match the spec

Source/core/dom/Element.h

Index: Source/core/dom/Element.h
diff --git a/Source/core/dom/Element.h b/Source/core/dom/Element.h
index d2b3a549be1dd74f06887f33c8a5f2d50ed41685..101d9c057b14938d0eca7752b5db245831954b17 100644
--- a/Source/core/dom/Element.h
+++ b/Source/core/dom/Element.h
@@ -60,6 +60,7 @@ class Locale;
 class MutableStylePropertySet;
 class PropertySetCSSStyleDeclaration;
 class PseudoElement;
+class ScrollToOptions;
 class ShadowRoot;
 class StylePropertySet;
 
@@ -182,12 +183,17 @@ public:
     virtual double scrollLeft();
     virtual double scrollTop();
     virtual void setScrollLeft(double);
-    virtual void setScrollLeft(const Dictionary& scrollOptionsHorizontal, ExceptionState&);
     virtual void setScrollTop(double);
-    virtual void setScrollTop(const Dictionary& scrollOptionsVertical, ExceptionState&);
     virtual int scrollWidth();
     virtual int scrollHeight();
 
+    virtual void scrollBy(double x, double y);
+    virtual void scrollBy(const ScrollToOptions&);
+    virtual void scrollTo(double x, double y);
+    virtual void scrollTo(const ScrollToOptions&);
+    void scroll(double x, double y) { scrollTo(x, y); }
+    void scroll(const ScrollToOptions& scrollToOptions) { scrollTo(scrollToOptions); }
+
     IntRect boundsInRootViewSpace();
 
     PassRefPtrWillBeRawPtr<ClientRectList> getClientRects();