Move enum MenuAnchorPosition to reduce deps on menu_item_view.h

ui/views/controls/menu/menu_scroll_view_container.cc

Index: ui/views/controls/menu/menu_scroll_view_container.cc
diff --git a/ui/views/controls/menu/menu_scroll_view_container.cc b/ui/views/controls/menu/menu_scroll_view_container.cc
index ea02917f94a18ff2c53edf9880988a40e74d6301..1712fbac613a4a69eb1d7c30849dd07fcd0b13c2 100644
--- a/ui/views/controls/menu/menu_scroll_view_container.cc
+++ b/ui/views/controls/menu/menu_scroll_view_container.cc
@@ -315,17 +315,16 @@ void MenuScrollViewContainer::CreateBubbleBorder() {
   set_background(new BubbleBackground(bubble_border_));
 }
 
-BubbleBorder::Arrow
-MenuScrollViewContainer::BubbleBorderTypeFromAnchor(
-    MenuItemView::AnchorPosition anchor) {
+BubbleBorder::Arrow MenuScrollViewContainer::BubbleBorderTypeFromAnchor(
+    MenuAnchorPosition anchor) {
   switch (anchor) {
-    case views::MenuItemView::BUBBLE_LEFT:
+    case MENU_ANCHOR_BUBBLE_LEFT:
       return BubbleBorder::RIGHT_CENTER;
-    case views::MenuItemView::BUBBLE_RIGHT:
+    case MENU_ANCHOR_BUBBLE_RIGHT:
       return BubbleBorder::LEFT_CENTER;
-    case views::MenuItemView::BUBBLE_ABOVE:
+    case MENU_ANCHOR_BUBBLE_ABOVE:
       return BubbleBorder::BOTTOM_CENTER;
-    case views::MenuItemView::BUBBLE_BELOW:
+    case MENU_ANCHOR_BUBBLE_BELOW:
       return BubbleBorder::TOP_CENTER;
     default:
       return BubbleBorder::NONE;