Mac: Do not call PopupMenuClient::popupDidHide in ExternalPopupMenu:show.

Source/web/ExternalPopupMenu.cpp

Index: Source/web/ExternalPopupMenu.cpp
diff --git a/Source/web/ExternalPopupMenu.cpp b/Source/web/ExternalPopupMenu.cpp
index a1075db6f0f969ffca5151f58335509cdd62bc17..70221f782ef3fb0df075b6613f9738e12db37673 100644
--- a/Source/web/ExternalPopupMenu.cpp
+++ b/Source/web/ExternalPopupMenu.cpp
@@ -64,9 +64,12 @@ ExternalPopupMenu::~ExternalPopupMenu()
 void ExternalPopupMenu::show(const FloatQuad& controlPosition, const IntSize&, int index)
 {
     IntRect rect(controlPosition.enclosingBoundingBox());
-    // WebCore reuses the PopupMenu of a page.
+    // WebCore reuses the PopupMenu of an element.
     // For simplicity, we do recreate the actual external popup everytime.
-    hide();
+    if (m_webExternalPopupMenu) {
+        m_webExternalPopupMenu->close();
+        m_webExternalPopupMenu = 0;
+    }
 
     WebPopupMenuInfo info;
     getPopupMenuInfo(&info);