Remove non-cros support from ash/common/system.

ash/common/system/user/tray_user_unittest.cc

Index: ash/common/system/user/tray_user_unittest.cc
diff --git a/ash/common/system/user/tray_user_unittest.cc b/ash/common/system/user/tray_user_unittest.cc
index ec22ad59687bba3f6808f6f914afb2cb54792f5e..ed0f5d0fff066725b4ab12161bc4a878cc533ef3 100644
--- a/ash/common/system/user/tray_user_unittest.cc
+++ b/ash/common/system/user/tray_user_unittest.cc
@@ -193,7 +193,6 @@ TEST_F(TrayUserTest, AccessibleLabelContainsMultiUserInfo) {
   EXPECT_EQ(ui::AX_ROLE_BUTTON, node_data.role);
 }
 
-#if defined(OS_CHROMEOS)
 // Make sure that in multi user mode the user panel can be activated and there
 // will be one panel for each user plus one additional separator at the end.
 // Note: the mouse watcher (for automatic closing upon leave) cannot be tested
@@ -279,6 +278,4 @@ TEST_F(TrayUserTest, MultiUserModeButtonClicks) {
   tray()->CloseSystemBubble();
 }
 
-#endif
-
 }  // namespace ash