chromeos: Remove AshTestBase::SupportsMultipleDisplays

ash/display/cursor_window_controller_unittest.cc

Index: ash/display/cursor_window_controller_unittest.cc
diff --git a/ash/display/cursor_window_controller_unittest.cc b/ash/display/cursor_window_controller_unittest.cc
index a2612e461d5d922a686f784a7f69c10d9acf08c4..bb87800245a4e03424d26eb0980edffbdfef3d90 100644
--- a/ash/display/cursor_window_controller_unittest.cc
+++ b/ash/display/cursor_window_controller_unittest.cc
@@ -65,9 +65,6 @@ class CursorWindowControllerTest : public test::AshTestBase {
 // Test that the composited cursor moves to another display when the real cursor
 // moves to another display.
 TEST_F(CursorWindowControllerTest, MoveToDifferentDisplay) {
-  if (!SupportsMultipleDisplays())
-    return;
-
   UpdateDisplay("200x200,200x200*2/r");
 
   WindowTreeHostManager* window_tree_host_manager =