mus: Add views_mus_interactive_ui_tests target

ui/views/mus/platform_test_helper_mus.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 "base/command_line.h"
 #include "base/memory/ptr_util.h"
 #include "base/run_loop.h"
 #include "services/shell/background/background_shell.h"
 #include "services/shell/background/tests/test_catalog_store.h"
 #include "services/shell/public/cpp/connector.h"
@@ skipping 48 matching lines @@
         &PlatformTestHelperMus::CreateNativeWidgetMus, base::Unretained(this),
         std::map<std::string, std::vector<uint8_t>>()));
   }
 
   ~PlatformTestHelperMus() override {
     WindowManagerConnection::Reset();
     // |app_| has a reference to us, destroy it while we are still valid.
     shell_connection_.reset();
   }
 
-  bool IsMus() const override { return true; }
-
  private:
   NativeWidget* CreateNativeWidgetMus(
       const std::map<std::string, std::vector<uint8_t>>& props,
       const Widget::InitParams& init_params,
       internal::NativeWidgetDelegate* delegate) {
     ui::ContextFactory* factory = aura::Env::GetInstance()->context_factory();
     aura::Env::GetInstance()->set_context_factory(nullptr);
     NativeWidget* result =
         WindowManagerConnection::Get()->CreateNativeWidgetMus(
             props, init_params, delegate);
     aura::Env::GetInstance()->set_context_factory(factory);
     return result;
   }
 
   std::unique_ptr<BackgroundShell> background_shell_;
   std::unique_ptr<shell::ShellConnection> shell_connection_;
   std::unique_ptr<DefaultShellClient> shell_client_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformTestHelperMus);
 };
 
 }  // namespace
 
 // static
 std::unique_ptr<PlatformTestHelper> PlatformTestHelper::Create() {
   return base::WrapUnique(new PlatformTestHelperMus);
 }
 
+// static
+bool PlatformTestHelper::IsMus() {
+  return true;
+}
+
 }  // namespace views