SVGTests should not leave detached elements in the tree

LayoutTests/svg/dynamic-updates/script-tests/SVGTextElement-svgdom-requiredFeatures.js

Index: LayoutTests/svg/dynamic-updates/script-tests/SVGTextElement-svgdom-requiredFeatures.js
diff --git a/LayoutTests/svg/dynamic-updates/script-tests/SVGTextElement-svgdom-requiredFeatures.js b/LayoutTests/svg/dynamic-updates/script-tests/SVGTextElement-svgdom-requiredFeatures.js
index ff5e83390164f6c886a1aaf364baaf169fc09acd..4023df12091ca6e8a2bc312da6dd6396f080861d 100644
--- a/LayoutTests/svg/dynamic-updates/script-tests/SVGTextElement-svgdom-requiredFeatures.js
+++ b/LayoutTests/svg/dynamic-updates/script-tests/SVGTextElement-svgdom-requiredFeatures.js
@@ -4,24 +4,25 @@
 createSVGTestCase();
 
 var textElement = createSVGElement("text");
+textElement.appendChild(document.createTextNode('Text'));
 
 rootSVGElement.appendChild(textElement);
 
 function repaintTest() {
     debug("Check that SVGTextElement is initially displayed");
-    shouldBeEqualToString("document.defaultView.getComputedStyle(textElement, null).display", "block");
+    shouldBeTrue("textElement.getBBox().width > 0");
     debug("Check that setting requiredFeatures to something invalid makes it not render");
     textElement.requiredFeatures.appendItem("http://www.w3.org/TR/SVG11/feature#BogusFeature");
-    shouldBeEqualToString("document.defaultView.getComputedStyle(textElement, null).display", "");
+    shouldBe("textElement.getBBox().width", "0");
     debug("Check that setting requiredFeatures to something valid makes it render again");
     textElement.requiredFeatures.replaceItem("http://www.w3.org/TR/SVG11/feature#Shape", 0);
-    shouldBeEqualToString("document.defaultView.getComputedStyle(textElement, null).display", "block");
+    shouldBeTrue("textElement.getBBox().width > 0");
     debug("Check that adding something valid to requiredFeatures keeps rendering the element");
     textElement.requiredFeatures.appendItem("http://www.w3.org/TR/SVG11/feature#Gradient");
-    shouldBeEqualToString("document.defaultView.getComputedStyle(textElement, null).display", "block");
+    shouldBeTrue("textElement.getBBox().width > 0");
     debug("Check that adding something invalid to requiredFeatures makes it not render");
     textElement.requiredFeatures.appendItem("http://www.w3.org/TR/SVG11/feature#BogusFeature");
-    shouldBeEqualToString("document.defaultView.getComputedStyle(textElement, null).display", "");
+    shouldBe("textElement.getBBox().width", "0");
 
     completeTest();
 }