Perform navigation policy check on UI thread for --site-per-process.

content/test/content_browser_test_utils_internal.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/test/content_browser_test_utils_internal.h"
+
+#include "content/browser/frame_host/frame_tree_node.h"
+#include "content/browser/frame_host/navigator.h"
+#include "content/test/test_frame_navigation_observer.h"
+#include "url/gurl.h"
+
+namespace content {
+
+void NavigateFrameToURL(FrameTreeNode* node, const GURL& url) {
+  TestFrameNavigationObserver observer(node);
+  NavigationController::LoadURLParams params(url);
+  params.transition_type = PageTransitionFromInt(PAGE_TRANSITION_LINK);
+  params.frame_tree_node_id = node->frame_tree_node_id();
+  node->navigator()->GetController()->LoadURLWithParams(params);
+  observer.Wait();
+}
+
+}  // namespace content