Removes code using mus client lib

ui/views/test/views_test_base.h

Index: ui/views/test/views_test_base.h
diff --git a/ui/views/test/views_test_base.h b/ui/views/test/views_test_base.h
index 74cfb8ea06fdf60ff023c057648f0022e6b4416e..ebdc44070cbe3f622a05d5f960f7dbb9c134c807 100644
--- a/ui/views/test/views_test_base.h
+++ b/ui/views/test/views_test_base.h
@@ -29,12 +29,9 @@ class ViewsTestBase : public PlatformTest {
   ViewsTestBase();
   ~ViewsTestBase() override;
 
-  // Whether the test is running under mus.
-  static bool IsMus();
-
   // Returns true if running aura-mus in a client configuration (not the window
   // manager).
-  static bool IsAuraMusClient();
+  static bool IsMus();
 
   // testing::Test:
   void SetUp() override;