Removes code using mus client lib

ui/views/event_monitor_unittest.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 "base/macros.h"
 #include "ui/events/test/event_generator.h"
 #include "ui/events/test/test_event_handler.h"
 #include "ui/views/event_monitor.h"
 #include "ui/views/test/widget_test.h"
 
 namespace views {
 namespace test {
 
 class EventMonitorTest : public WidgetTest {
  public:
   EventMonitorTest() : widget_(nullptr) {}
 
   // testing::Test:
   void SetUp() override {
     WidgetTest::SetUp();
     widget_ = CreateTopLevelNativeWidget();
     widget_->SetSize(gfx::Size(100, 100));
     widget_->Show();
-    if (IsMus() || IsAuraMusClient()) {
+    if (IsMus()) {
       generator_.reset(
           new ui::test::EventGenerator(widget_->GetNativeWindow()));
     } else {
       generator_.reset(new ui::test::EventGenerator(
           GetContext(), widget_->GetNativeWindow()));
     }
     generator_->set_target(ui::test::EventGenerator::Target::APPLICATION);
   }
   void TearDown() override {
     widget_->CloseNow();
@@ skipping 40 matching lines @@
 
   generator_->ClickLeftButton();
   EXPECT_EQ(0, handler_.num_mouse_events());
 
   monitor.reset();
   widget2->CloseNow();
 }
 
 }  // namespace test
 }  // namespace views