Multi-select <select> in 'external popup window'

content/browser/web_contents/web_contents_view_mac.mm

Index: content/browser/web_contents/web_contents_view_mac.mm
diff --git a/content/browser/web_contents/web_contents_view_mac.mm b/content/browser/web_contents/web_contents_view_mac.mm
index b03012f43d9b5f51b0097d3fd1e7f93c264dc4f7..8ceb079948baa7295abdf0146a74a7b192158e20 100644
--- a/content/browser/web_contents/web_contents_view_mac.mm
+++ b/content/browser/web_contents/web_contents_view_mac.mm
@@ -10,6 +10,7 @@
 
 #import "base/mac/scoped_sending_event.h"
 #import "base/message_pump_mac.h"
+#include "content/browser/renderer_host/popup_menu_helper_mac.h"
 #include "content/browser/renderer_host/render_view_host_factory.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
@@ -287,6 +288,21 @@ void WebContentsViewMac::ShowContextMenu(
     DLOG(ERROR) << "Cannot show context menus without a delegate.";
 }
 
+// Display a popup menu for WebKit using Cocoa widgets.
+void WebContentsViewMac::ShowPopupMenu(
+    const gfx::Rect& bounds,
+    int item_height,
+    double item_font_size,
+    int selected_item,
+    const std::vector<WebMenuItem>& items,
+    bool right_aligned,
+    bool allow_multiple_selection) {
+  PopupMenuHelper popup_menu_helper(web_contents_->GetRenderViewHost());
+  popup_menu_helper.ShowPopupMenu(bounds, item_height, item_font_size,
+                                  selected_item, items, right_aligned,
+                                  allow_multiple_selection);
+}
+
 bool WebContentsViewMac::IsEventTracking() const {
   return base::MessagePumpMac::IsHandlingSendEvent();
 }