Use the same task queue for immediate and delayed tasks

content/shell/renderer/layout_test/webkit_test_runner.cc

Index: content/shell/renderer/layout_test/webkit_test_runner.cc
diff --git a/content/shell/renderer/layout_test/webkit_test_runner.cc b/content/shell/renderer/layout_test/webkit_test_runner.cc
index 0bda738056669bf608b6412106b20fa9c36ed6b0..b030c97a74536028c24e5d00cac4063f2f521956 100644
--- a/content/shell/renderer/layout_test/webkit_test_runner.cc
+++ b/content/shell/renderer/layout_test/webkit_test_runner.cc
@@ -49,6 +49,7 @@
 #include "third_party/WebKit/public/platform/WebRect.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
 #include "third_party/WebKit/public/platform/WebString.h"
+#include "third_party/WebKit/public/platform/WebThread.h"
 #include "third_party/WebKit/public/platform/WebURL.h"
 #include "third_party/WebKit/public/platform/WebURLError.h"
 #include "third_party/WebKit/public/platform/WebURLRequest.h"
@@ -88,6 +89,7 @@ using blink::WebURLError;
 using blink::WebURLRequest;
 using blink::WebScreenOrientationType;
 using blink::WebTestingSupport;
+using blink::WebThread;
 using blink::WebVector;
 using blink::WebView;
 
@@ -95,11 +97,16 @@ namespace content {
 
 namespace {
 
-void InvokeTaskHelper(void* context) {
-  WebTask* task = reinterpret_cast<WebTask*>(context);
-  task->run();
-  delete task;
-}
+class InvokeTaskHelper : public WebThread::Task {
+ public:
+  InvokeTaskHelper(scoped_ptr<WebTask> task) : task_(task.Pass()) {}
+
+  // WebThread::Task implementation:
+  void run() override { task_->run(); }
+
+ private:
+  scoped_ptr<WebTask> task_;
+};
 
 class SyncNavigationStateVisitor : public RenderViewVisitor {
  public:
@@ -246,14 +253,13 @@ void WebKitTestRunner::PrintMessage(const std::string& message) {
 }
 
 void WebKitTestRunner::PostTask(WebTask* task) {
-  Platform::current()->callOnMainThread(InvokeTaskHelper, task);
+  Platform::current()->currentThread()->postTask(
+      new InvokeTaskHelper(make_scoped_ptr(task)));
 }
 
 void WebKitTestRunner::PostDelayedTask(WebTask* task, long long ms) {
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      base::Bind(&WebTask::run, base::Owned(task)),
-      base::TimeDelta::FromMilliseconds(ms));
+  Platform::current()->currentThread()->postDelayedTask(
+      new InvokeTaskHelper(make_scoped_ptr(task)), ms);
 }
 
 WebString WebKitTestRunner::RegisterIsolatedFileSystem(