Move LayoutAndPaintAsyncThen to a separate compilation unit.

components/test_runner/layout_and_paint_async_then.cc

Index: components/test_runner/layout_and_paint_async_then.cc
diff --git a/components/test_runner/layout_and_paint_async_then.cc b/components/test_runner/layout_and_paint_async_then.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b2834d249d771d07ecc62049b2b20b37db25f629
--- /dev/null
+++ b/components/test_runner/layout_and_paint_async_then.cc
@@ -0,0 +1,60 @@
+// Copyright 2016 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 "components/test_runner/layout_and_paint_async_then.h"
+
+#include "base/callback.h"
+#include "base/trace_event/trace_event.h"
+#include "third_party/WebKit/public/platform/WebLayoutAndPaintAsyncCallback.h"
+#include "third_party/WebKit/public/web/WebPagePopup.h"
+#include "third_party/WebKit/public/web/WebWidget.h"
+
+namespace test_runner {
+
+namespace {
+
+class LayoutAndPaintCallback : public blink::WebLayoutAndPaintAsyncCallback {
+ public:
+  LayoutAndPaintCallback(const base::Closure& callback)
+      : callback_(callback), wait_for_popup_(false) {}
+  virtual ~LayoutAndPaintCallback() {}
+
+  void set_wait_for_popup(bool wait) { wait_for_popup_ = wait; }
+
+  // WebLayoutAndPaintAsyncCallback implementation.
+  void didLayoutAndPaint() override;
+
+ private:
+  base::Closure callback_;
+  bool wait_for_popup_;
+};
+
+void LayoutAndPaintCallback::didLayoutAndPaint() {
+  TRACE_EVENT0("shell", "LayoutAndPaintCallback::didLayoutAndPaint");
+  if (wait_for_popup_) {
+    wait_for_popup_ = false;
+    return;
+  }
+
+  if (!callback_.is_null())
+    callback_.Run();
+  delete this;
+}
+
+}  // namespace
+
+void LayoutAndPaintAsyncThen(blink::WebWidget* web_widget,
+                             const base::Closure& callback) {
+  TRACE_EVENT0("shell", "LayoutAndPaintAsyncThen");
+
+  LayoutAndPaintCallback* layout_and_paint_callback =
+      new LayoutAndPaintCallback(callback);
+  web_widget->layoutAndPaintAsync(layout_and_paint_callback);
+  if (blink::WebPagePopup* popup = web_widget->pagePopup()) {
+    layout_and_paint_callback->set_wait_for_popup(true);
+    popup->layoutAndPaintAsync(layout_and_paint_callback);
+  }
+}
+
+}  // namespace test_runner