Generalizing architecture for screenshot testing

chrome/browser/chromeos/login/screenshot_testing_mixin.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 "chrome/browser/chromeos/login/screenshot_testing_mixin.h"
+
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_notification_types.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_types.h"
+#include "ui/compositor/compositor_switches.h"
+
+namespace chromeos {
+
+ScreenshotTestingMixin::ScreenshotTestingMixin() {
+}
+
+ScreenshotTestingMixin::~ScreenshotTestingMixin() {
+}
+
+void ScreenshotTestingMixin::SetUpInProcessBrowserTestFixture() {
+  enable_test_screenshots_ = screenshot_tester_.TryInitialize();
+}
+
+void ScreenshotTestingMixin::SetUpCommandLine(base::CommandLine* command_line) {
+  if (enable_test_screenshots_) {
+    command_line->AppendSwitch(switches::kEnablePixelOutputInTests);
+    command_line->AppendSwitch(switches::kUIEnableImplSidePainting);
+  }
+}
+
+void ScreenshotTestingMixin::RunScreenshotTesting(
+    const std::string& test_name) {
+  if (enable_test_screenshots_) {
+    SynchronizeAnimationLoadWithCompositor();
+    screenshot_tester_.Run(test_name);
+  }
+}
+
+// Current implementation is a mockup.
+// It simply waits for 5 seconds, assuming that this time is enough for
+// animation to load completely.
+// TODO(elizavetai): Replace this temporary hack with getting a
+// valid notification from compositor.
+void ScreenshotTestingMixin::SynchronizeAnimationLoadWithCompositor() {
+  base::RunLoop waiter;
+  animation_waiter_quitter_ = waiter.QuitClosure();
+  timer_.Start(FROM_HERE,
+               base::TimeDelta::FromSeconds(5),
+               this,
+               &ScreenshotTestingMixin::HandleAnimationLoad);
+  waiter.Run();
+}
+
+void ScreenshotTestingMixin::HandleAnimationLoad() {
+  timer_.Stop();
+  content::BrowserThread::PostTask(
+      content::BrowserThread::UI, FROM_HERE, animation_waiter_quitter_);
+}
+
+}  // namespace chromeos