DevTools: do not use Internals for inspector highlight tests.

LayoutTests/http/tests/inspector/elements-test.js

-function getInspectorHighlightJSON(nodeId, opt_frameId)
-{
-    var doc = document;
-    if (opt_frameId)
-        doc = document.getElementById(opt_frameId).contentDocument;
-    return window.internals.inspectorHighlightJSON(doc.getElementById(nodeId));
-}
-
 var initialize_ElementTest = function() {
 
 InspectorTest.preloadPanel("elements");
 
 InspectorTest.inlineStyleSection = function()
 {
     return WebInspector.panels.elements.sidebarPanes.styles.sections[0][0];
 }
 
 InspectorTest.computedStyleSection = function()
@@ skipping 852 matching lines @@
 
 function onBlankSection(selector, callback)
 {
     var section = InspectorTest.firstMatchedStyleSection();
     if (typeof selector === "string")
         section._selectorElement.textContent = selector;
     section._selectorElement.dispatchEvent(InspectorTest.createKeyEvent("Enter"));
     InspectorTest.waitForSelectorCommitted(callback.bind(null, section));
 }
 
-InspectorTest.dumpInspectorHighlightJSON = function(nodeId, callback, opt_frameId)
+InspectorTest.dumpInspectorHighlightJSON = function(idValue, callback)
 {
-    function innerCallback(result)
+    InspectorTest.nodeWithId(idValue, nodeResolved);
+
+    function nodeResolved(node)
     {
-        InspectorTest.addResult(nodeId + ": " + result.description);
+        InspectorTest.DOMAgent.getHighlightObjectForTest(node.id, report);
+    }
+
+    function report(error, result)
+    {
+        InspectorTest.addResult(idValue + JSON.stringify(result, null, 2));
         callback();
     }
-    opt_frameId = opt_frameId || "";
-    InspectorTest.evaluateInPage("getInspectorHighlightJSON(\"" + nodeId + "\", \"" + opt_frameId + "\")", innerCallback);
 }
 
 };