Revert of Fix for menus blocking user activity detection (Retry).

ui/ozone/platform/test/ozone_platform_test.cc

Index: ui/ozone/platform/test/ozone_platform_test.cc
diff --git a/ui/ozone/platform/test/ozone_platform_test.cc b/ui/ozone/platform/test/ozone_platform_test.cc
index d94fde97707f0cdd31e5db7ac966355656f59a52..fce3a9d3cd3fa4382abd9dfa36ece6b2726fb827 100644
--- a/ui/ozone/platform/test/ozone_platform_test.cc
+++ b/ui/ozone/platform/test/ozone_platform_test.cc
@@ -24,17 +24,6 @@
 namespace ui {
 
 namespace {
-
-// A test implementation of PlatformEventSource that we can instantiate to make
-// sure that the PlatformEventSource has an instance while in unit tests.
-class TestPlatformEventSource : public ui::PlatformEventSource {
- public:
-  TestPlatformEventSource() {}
-  ~TestPlatformEventSource() override {}
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(TestPlatformEventSource);
-};
 
 // OzonePlatform for testing
 //
@@ -78,7 +67,7 @@
     window_manager_->Initialize();
     // This unbreaks tests that create their own.
     if (!PlatformEventSource::GetInstance())
-      platform_event_source_.reset(new TestPlatformEventSource);
+      platform_event_source_ = PlatformEventSource::CreateDefault();
     KeyboardLayoutEngineManager::SetKeyboardLayoutEngine(
         make_scoped_ptr(new StubKeyboardLayoutEngine()));