DevTools: Support XHR async call stacks in the debugger.

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

Index: LayoutTests/http/tests/inspector/debugger-test.js
diff --git a/LayoutTests/http/tests/inspector/debugger-test.js b/LayoutTests/http/tests/inspector/debugger-test.js
index 21d535568fa5df938ea51a053cd0d494f88b2732..6ffa21789727402a3a88eb69b91f4149052a8a60 100644
--- a/LayoutTests/http/tests/inspector/debugger-test.js
+++ b/LayoutTests/http/tests/inspector/debugger-test.js
@@ -83,6 +83,43 @@ InspectorTest.runTestFunctionAndWaitUntilPaused = function(callback)
     InspectorTest.waitUntilPaused(callback);
 };
 
+InspectorTest.runAsyncCallStacksTest = function(totalDebuggerStatements, maxAsyncCallStackDepth)
+{
+    maxAsyncCallStackDepth = maxAsyncCallStackDepth || 4;

[yurys, 2013/12/23 09:11:57]

Please make it a required parameter for better readability and less implicit
assumptions.

[aandrey, 2013/12/23 12:09:38]

Done.

+
+    InspectorTest.setQuiet(true);
+    InspectorTest.startDebuggerTest(step1);
+
+    function step1()
+    {
+        DebuggerAgent.setAsyncCallStackDepth(maxAsyncCallStackDepth, step2);
+    }
+
+    function step2()
+    {
+        InspectorTest.runTestFunctionAndWaitUntilPaused(didPaused);
+    }
+
+    var step = 0;
+    var callStacksOutput = [];
+    function didPaused(callFrames, reason, breakpointIds, asyncStackTrace)
+    {
+        ++step;
+        InspectorTest.beginResultBufferring();

[yurys, 2013/12/23 09:11:57]

I must have overlooked this begin/endResultBuffering in one of the previous
patches sorry about that, but it seems to be adding unnecessary complexity to
the test framework. Can you change the utility code so that it accepted explicit
output buffer it it needs one or return accumulated output as function result
and didn't require changing basic output behavior?

[aandrey, 2013/12/23 12:09:38]

Done.

+        InspectorTest.captureStackTrace(callFrames, asyncStackTrace);
+        callStacksOutput.push(InspectorTest.endResultBufferring());
+
+        if (step < totalDebuggerStatements) {
+            InspectorTest.resumeExecution(InspectorTest.waitUntilPaused.bind(InspectorTest, didPaused));
+        } else {
+            InspectorTest.addResult("Captured call stacks in no particular order:");
+            callStacksOutput.sort();
+            InspectorTest.addResults(callStacksOutput);
+            InspectorTest.completeDebuggerTest();
+        }
+    }
+};
+
 InspectorTest.waitUntilPausedNextTime = function(callback)
 {
     InspectorTest._waitUntilPausedCallback = InspectorTest.safeWrap(callback);
@@ -151,7 +188,7 @@ InspectorTest.captureStackTrace = function(callFrames, asyncStackTrace, options)
     while (asyncStackTrace) {
         InspectorTest.addResult("    [" + (asyncStackTrace.description || "Async Call") + "]");
         printCallFrames(asyncStackTrace.callFrames);
-        if (asyncStackTrace.callFrames[0].functionName === "testFunction")
+        if (asyncStackTrace.callFrames.peekLast().functionName === "testFunction")
             break;
         asyncStackTrace = asyncStackTrace.asyncStackTrace;
     }