Remove obsolete scale related APIs for cursor

ash/wm/ash_native_cursor_manager.cc

Index: ash/wm/ash_native_cursor_manager.cc
diff --git a/ash/wm/ash_native_cursor_manager.cc b/ash/wm/ash_native_cursor_manager.cc
index d9f4b6af6e449c0bc7c9fb8f1c7a690a90426cfc..98078ace1c533a6937f89f7ecc64fce5c7023509 100644
--- a/ash/wm/ash_native_cursor_manager.cc
+++ b/ash/wm/ash_native_cursor_manager.cc
@@ -120,16 +120,6 @@ void AshNativeCursorManager::SetCursorSet(
 #endif
 }
 
-void AshNativeCursorManager::SetScale(
-    float scale,
-    ::wm::NativeCursorManagerDelegate* delegate) {
-  image_cursors_->SetScale(scale);
-  delegate->CommitScale(scale);
-
-  // Sets the cursor to reflect the scale change immediately.
-  SetCursor(delegate->GetCursor(), delegate);
-}
-
 void AshNativeCursorManager::SetVisibility(
     bool visible,
     ::wm::NativeCursorManagerDelegate* delegate) {