Do not implement EventTarget on SVGElementInstance

LayoutTests/svg/custom/resources/use-instanceRoot-event-bubbling.js

 window.testIsAsync = true;
 description("Tests whether SVG event bubbling works across shadow trees.");
 
 var svgNS = "http://www.w3.org/2000/svg";
 var xhtmlNS = "http://www.w3.org/1999/xhtml";
 var expected = new Array(4);
 var tests = 4;
 var counter = 0;
 var eventCounter = 0;
 
@@ skipping 23 matching lines @@
     ++eventCounter;
 
     if (label == counter)
         setTimeout(label == tests ? finishTest : nextTest, 0);
 }
 
 function finishTest()
 {
     successfullyParsed = true;
 
-    use.instanceRoot.correspondingElement.setAttribute("fill", "green");
+    rectContainer.setAttribute("fill", "green");
     shouldBeTrue("successfullyParsed");
     debug('<br /><span class="pass">TEST COMPLETE</span>');
 
     finishRepaintTest();
 }
 
 function nextTest()
 {
     eventCounter = 0;
     ++counter;
 
     switch (counter) {
     case 1:
         rect.onclick = function(evt) { eventHandler(evt, 1); };
-        expected[0] = "[EventHandler 1] type: click phase: AT_TARGET target: [object SVGElementInstance] (id: rect) currentTarget: [object SVGElementInstance] (id: rect)";
+        expected[0] = "[EventHandler 1] type: click phase: AT_TARGET target: [object SVGUseElement] (id: use) currentTarget: [object SVGUseElement] (id: use)";
         testListeners();
         break;
     case 2:
         rectContainer.addEventListener("click", function(evt) { eventHandler(evt, 2) }, false);
-        expected[1] = "[EventHandler 2] type: click phase: BUBBLING target: [object SVGElementInstance] (id: rect) currentTarget: [object SVGElementInstance] (id: rectParent)";    
+        expected[1] = "[EventHandler 2] type: click phase: AT_TARGET target: [object SVGUseElement] (id: use) currentTarget: [object SVGUseElement] (id: use)";
         testListeners();
         break;
     case 3:
         use.setAttribute("onclick", "eventHandler(evt, 3)");
-        expected[2] = "[EventHandler 3] type: click phase: BUBBLING target: [object SVGElementInstance] (id: rect) currentTarget: [object SVGUseElement] (id: use)";
+        expected[2] = "[EventHandler 3] type: click phase: AT_TARGET target: [object SVGUseElement] (id: use) currentTarget: [object SVGUseElement] (id: use)";
         testListeners();
         break;
     case 4:
         useContainer.onclick = function(evt) { eventHandler(evt, 4) };
-        expected[3] = "[EventHandler 4] type: click phase: BUBBLING target: [object SVGElementInstance] (id: rect) currentTarget: [object SVGGElement] (id: useParent)";
+        expected[3] = "[EventHandler 4] type: click phase: BUBBLING target: [object SVGUseElement] (id: use) currentTarget: [object SVGGElement] (id: useParent)";
         testListeners();
         break;
     }
 }
 
 function testListeners()
 {
     if (window.eventSender) {
         eventSender.mouseMoveTo(50, 50);
         eventSender.mouseDown();
@@ skipping 29 matching lines @@
 svg.appendChild(useContainer);
 
 var use = document.createElementNS(svgNS, "use");
 use.id = "use";
 use.href.baseVal = "#rectParent";
 useContainer.appendChild(use);
 
 function repaintTest() {
     nextTest();
 }