Fixed the Touchscreen.TouchEventsEnabled histogram to record the correct values on X11 and Ozone ba…

chrome/browser/metrics/chrome_browser_main_extra_parts_metrics_unittest.cc

Index: chrome/browser/metrics/chrome_browser_main_extra_parts_metrics_unittest.cc
diff --git a/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics_unittest.cc b/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ffc88bd07c2a9c25f38709114146dafe17388b45
--- /dev/null
+++ b/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics_unittest.cc
@@ -0,0 +1,127 @@
+// Copyright 2015 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/metrics/chrome_browser_main_extra_parts_metrics.h"
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/message_loop/message_loop.h"
+#include "base/test/histogram_tester.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/events/test/device_data_manager_test_api.h"
+#include "ui/gfx/geometry/size.h"
+#include "ui/gfx/screen.h"
+#include "ui/gfx/test/test_screen.h"
+
+namespace {
+
+const char kTouchEventsEnabledHistogramName[] =
+    "Touchscreen.TouchEventsEnabled";
+
+}  // namespace
+
+class ChromeBrowserMainExtraPartsMetricsTest : public testing::Test {
+ public:
+  ChromeBrowserMainExtraPartsMetricsTest();
+  ~ChromeBrowserMainExtraPartsMetricsTest() override;
+
+ protected:
+  // Test API wrapping |device_data_manager_|.
+  ui::test::DeviceDataManagerTestAPI device_data_manager_test_api_;
+
+ private:
+  // Required by a ChromeBrowserMainExtraPartsMetrics test target.
+  base::MessageLoop message_loop_;
+
+  // Dummy screen required by a ChromeBrowserMainExtraPartsMetrics test target.
+  gfx::test::TestScreen test_screen_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeBrowserMainExtraPartsMetricsTest);
+};
+
+ChromeBrowserMainExtraPartsMetricsTest::ChromeBrowserMainExtraPartsMetricsTest()
+    : device_data_manager_test_api_() {
+  device_data_manager_test_api_.CreateDeviceDataManagerInstance();
+  gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE, &test_screen_);
+}
+
+ChromeBrowserMainExtraPartsMetricsTest::
+    ~ChromeBrowserMainExtraPartsMetricsTest() {
+  gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE, nullptr);
+}
+
+// Verify a TouchEventsEnabled value isn't recorded during construction.
+TEST_F(ChromeBrowserMainExtraPartsMetricsTest,
+       VerifyTouchEventsEnabledIsNotRecordedAfterConstruction) {
+  base::HistogramTester histogram_tester;
+  ChromeBrowserMainExtraPartsMetrics test_target;
+  histogram_tester.ExpectTotalCount(kTouchEventsEnabledHistogramName, 0);
+}
+
+#if defined(USE_OZONE) || defined(USE_X11)
+
+// Verify a TouchEventsEnabled value isn't recorded during PostBrowserStart if
+// the device scan hasn't completed yet.
+TEST_F(ChromeBrowserMainExtraPartsMetricsTest,
+       VerifyTouchEventsEnabledIsNotRecordedAfterPostBrowserStart) {
+  base::HistogramTester histogram_tester;
+
+  ChromeBrowserMainExtraPartsMetrics test_target;
+
+  test_target.PostBrowserStart();
+  histogram_tester.ExpectTotalCount(kTouchEventsEnabledHistogramName, 0);
+}
+
+// Verify a TouchEventsEnabled value is recorded during PostBrowserStart if the
+// device scan has already completed.
+TEST_F(ChromeBrowserMainExtraPartsMetricsTest,
+       VerifyTouchEventsEnabledIsRecordedAfterPostBrowserStart) {
+  base::HistogramTester histogram_tester;
+
+  device_data_manager_test_api_.OnDeviceListsComplete();
+
+  ChromeBrowserMainExtraPartsMetrics test_target;
+
+  test_target.PostBrowserStart();
+  histogram_tester.ExpectTotalCount(kTouchEventsEnabledHistogramName, 1);
+}
+
+// Verify a TouchEventsEnabled value is recorded when an asynchronous device
+// scan completes.
+TEST_F(ChromeBrowserMainExtraPartsMetricsTest,
+       VerifyTouchEventsEnabledIsRecordedWhenDeviceListsComplete) {
+  base::HistogramTester histogram_tester;
+  ChromeBrowserMainExtraPartsMetrics test_target;
+
+  test_target.PostBrowserStart();
+  device_data_manager_test_api_.NotifyObserversDeviceListsComplete();
+  histogram_tester.ExpectTotalCount(kTouchEventsEnabledHistogramName, 1);
+}
+
+// Verify a TouchEventsEnabled value is only recorded once if multiple
+// asynchronous device scans happen.
+TEST_F(ChromeBrowserMainExtraPartsMetricsTest,
+       VerifyTouchEventsEnabledIsOnlyRecordedOnce) {
+  base::HistogramTester histogram_tester;
+  ChromeBrowserMainExtraPartsMetrics test_target;
+
+  test_target.PostBrowserStart();
+  device_data_manager_test_api_.NotifyObserversDeviceListsComplete();
+  device_data_manager_test_api_.NotifyObserversDeviceListsComplete();
+  histogram_tester.ExpectTotalCount(kTouchEventsEnabledHistogramName, 1);
+}
+
+#else
+
+// Verify a TouchEventsEnabled value is recorded during PostBrowserStart.
+TEST_F(ChromeBrowserMainExtraPartsMetricsTest,
+       VerifyTouchEventsEnabledIsRecordedAfterPostBrowserStart) {
+  base::HistogramTester histogram_tester;
+  ChromeBrowserMainExtraPartsMetrics test_target;
+
+  test_target.PostBrowserStart();
+  histogram_tester.ExpectTotalCount(kTouchEventsEnabledHistogramName, 1);
+}
+
+#endif  // defined(USE_OZONE) || defined(USE_X11)