[svg] Make svgView override existing data selectively

Source/core/svg/SVGViewSpec.h

Index: Source/core/svg/SVGViewSpec.h
diff --git a/Source/core/svg/SVGViewSpec.h b/Source/core/svg/SVGViewSpec.h
index e40e37ff73c650419514d973036feb3a81d4eb48..c4a393eab97c355924da48e86a69952ce9fd0283 100644
--- a/Source/core/svg/SVGViewSpec.h
+++ b/Source/core/svg/SVGViewSpec.h
@@ -45,6 +45,7 @@ public:
     bool parseViewSpec(const String&);
     void reset();
     void detachContextElement();
+    template<typename T> void inheritViewAttributesFromElement(T*);
 
     // JS API
     SVGTransformList* transform() { return m_transform ? m_transform->baseValue() : 0; }
@@ -73,6 +74,21 @@ private:
     String m_viewTargetString;
 };
 
+template <typename T>
+void SVGViewSpec::inheritViewAttributesFromElement(T* inheritFromElement)
+{
+    if (inheritFromElement->hasAttribute(SVGNames::viewBoxAttr))
+        viewBox()->baseValue()->setValue(inheritFromElement->viewBox()->currentValue()->value());
+
+    if (inheritFromElement->hasAttribute(SVGNames::preserveAspectRatioAttr)) {
+        preserveAspectRatio()->baseValue()->setAlign(inheritFromElement->preserveAspectRatio()->currentValue()->align());
+        preserveAspectRatio()->baseValue()->setMeetOrSlice(inheritFromElement->preserveAspectRatio()->currentValue()->meetOrSlice());
+    }
+
+    if (inheritFromElement->hasAttribute(SVGNames::zoomAndPanAttr))
+        setZoomAndPan(inheritFromElement->zoomAndPan());
+}
+
 } // namespace blink
 
 #endif // SVGViewSpec_h