[SVG2] Add tabindex handling in svg.

Source/core/svg/SVGElement.h

Index: Source/core/svg/SVGElement.h
diff --git a/Source/core/svg/SVGElement.h b/Source/core/svg/SVGElement.h
index 1b397d91290649c5bf476a409090d4ccebeff5a8..4fc6d5b93da90d50ca4206058e97bf817018ef5b 100644
--- a/Source/core/svg/SVGElement.h
+++ b/Source/core/svg/SVGElement.h
@@ -51,6 +51,8 @@ class SVGElement : public Element {
 public:
     virtual ~SVGElement();
 
+    virtual short tabIndex() const OVERRIDE;
+
     bool isOutermostSVGSVGElement() const;
 
     virtual String title() const OVERRIDE;
@@ -195,13 +197,14 @@ private:
     RenderStyle* computedStyle(PseudoId = NOPSEUDO);
     virtual RenderStyle* virtualComputedStyle(PseudoId pseudoElementSpecifier = NOPSEUDO) OVERRIDE FINAL { return computedStyle(pseudoElementSpecifier); }
     virtual void willRecalcStyle(StyleRecalcChange) OVERRIDE;
-    virtual bool isKeyboardFocusable() const OVERRIDE;
 
     void buildPendingResourcesIfNeeded();
 
     void mapInstanceToElement(SVGElementInstance*);
     void removeInstanceMapping(SVGElementInstance*);
 
+    bool supportsSpatialNavigationFocus() const;
+
     void cleanupAnimatedProperties();
     friend class CleanUpAnimatedPropertiesCaller;