DevTools: Support asynchronous call stacks on backend.

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

 var initialize_InspectorTest = function() {
 
 var results = [];
 var resultsSynchronized = false;
 
 function consoleOutputHook(messageType)
 {
     InspectorTest.addResult(messageType + ": " + Array.prototype.slice.call(arguments, 1));
 }
 
@@ skipping 76 matching lines @@
 }
 
 InspectorTest.check = function(passCondition, failureText)
 {
     if (!passCondition)
         InspectorTest.addResult("FAIL: " + failureText);
 }
 
 InspectorTest.addResult = function(text)
 {
+    if (InspectorTest._resultBufferring) {
+        InspectorTest._resultBufferringContent += text + "\n";
+        return;
+    }
     results.push(text);
     if (resultsSynchronized)
         InspectorTest.Output.addResult(text);
     else {
         InspectorTest.Output.clearResults();
         for (var i = 0; i < results.length; ++i)
             InspectorTest.Output.addResult(results[i]);
         resultsSynchronized = true;
     }
 }
 
+InspectorTest.beginResultBufferring = function()
+{
+    InspectorTest._resultBufferring = true;
+    InspectorTest._resultBufferringContent = "";
+}
+
+InspectorTest.endResultBufferring = function()
+{
+    var result = InspectorTest._resultBufferringContent || "";
+    delete InspectorTest._resultBufferring;
+    delete InspectorTest._resultBufferringContent;
+    return result;
+}
+
 InspectorTest.addResults = function(textArray)
 {
     if (!textArray)
         return;
     for (var i = 0, size = textArray.length; i < size; ++i)
         InspectorTest.addResult(textArray[i]);
 }
 
 function onError(event)
 {
@@ skipping 516 matching lines @@
     evaluateInWebInspector: function(callId, script)
     {
         window.opener.postMessage(["evaluateInWebInspector", callId, script], "*");
     },
 
     display: function() { }
 }
 
 if (!window.testRunner && window.opener)
     window.testRunner = new StandaloneTestRunnerStub();