Removes code using mus client lib

ui/views/mus/clipboard_unittest.cc

 // 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 "ui/views/mus/clipboard_mus.h"
 
 #include "base/message_loop/message_loop.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/events/platform/platform_event_source.h"
-#include "ui/views/mus/window_manager_connection.h"
+#include "ui/views/mus/mus_client.h"
 #include "ui/views/test/scoped_views_test_helper.h"
 
 namespace ui {
 
 // So we can't make ScopedViewsTestHelper a global. We must set up
 // ScopedViewsTestHelper on every test (which will create the connection to
 // mus). And we can't modify PlatformClipboardTraits to not be a pure static
 // struct. So to solve these lifetime issues, create an adapter that owns the
 // ScopedViewsTestHelper and then .
 class ForwardingTestingClipboard : public ui::Clipboard {
  public:
   ForwardingTestingClipboard()
       : test_helper_(new views::ScopedViewsTestHelper),
         clipboard_to_test_(Clipboard::GetForCurrentThread()) {
     // If we don't have a window manager connection, we will get the default
     // platform clipboard instead.
-    EXPECT_TRUE(views::WindowManagerConnection::Exists());
+    EXPECT_TRUE(views::MusClient::Exists());
   }
 
   ~ForwardingTestingClipboard() override {
     Clipboard::DestroyClipboardForCurrentThread();
   }
 
   void Destroy() {
     delete this;
   }
 
@@ skipping 98 matching lines @@
   static void Destroy(Clipboard* clipboard) {
     static_cast<ForwardingTestingClipboard*>(clipboard)->Destroy();
   }
 };
 
 using TypesToTest = PlatformClipboardTraits;
 
 }  // namespace ui
 
 #include "ui/base/clipboard/clipboard_test_template.h"