Don't allow drop to panels (pop-ups) in ChromeOS.

chrome/browser/views/tab_contents/tab_contents_view_gtk.cc

Index: chrome/browser/views/tab_contents/tab_contents_view_gtk.cc
diff --git a/chrome/browser/views/tab_contents/tab_contents_view_gtk.cc b/chrome/browser/views/tab_contents/tab_contents_view_gtk.cc
index d6fd5dbc6d0d227978a425e8d27ae5098c6f0d67..55f2a32aa789357b68fdfb4ebb851dd938a8186d 100644
--- a/chrome/browser/views/tab_contents/tab_contents_view_gtk.cc
+++ b/chrome/browser/views/tab_contents/tab_contents_view_gtk.cc
@@ -189,7 +189,8 @@ RenderWidgetHostView* TabContentsViewGtk::CreateViewForWidget(
                         GDK_POINTER_MOTION_MASK);
 
   // Renderer target DnD.
-  drag_dest_.reset(new WebDragDestGtk(tab_contents(), view->native_view()));
+  if (tab_contents()->ShouldAcceptDragAndDrop())
+    drag_dest_.reset(new WebDragDestGtk(tab_contents(), view->native_view()));
 
   gtk_fixed_put(GTK_FIXED(GetNativeView()), view->native_view(), 0, 0);
   return view;
@@ -320,7 +321,8 @@ void TabContentsViewGtk::RestoreFocus() {
 }
 
 void TabContentsViewGtk::UpdateDragCursor(WebDragOperation operation) {
-  drag_dest_->UpdateDragStatus(operation);
+  if (drag_dest_.get())
+    drag_dest_->UpdateDragStatus(operation);
 }
 
 void TabContentsViewGtk::GotFocus() {