Change URL back to the previous one if the typed URL causes file download....

chrome/browser/tab_contents/tab_util.cc

Index: chrome/browser/tab_contents/tab_util.cc
===================================================================
--- chrome/browser/tab_contents/tab_util.cc	(revision 16844)
+++ chrome/browser/tab_contents/tab_util.cc	(working copy)
@@ -29,6 +29,11 @@
 
 TabContents* tab_util::GetTabContentsByID(int render_process_id,
                                           int render_view_id) {
+  // Ensures that that this method is only ever called on the UI thread.
+
+  // TODO(yuzo): Fix the callers and uncomment the following.
+  // DCHECK_EQ(MessageLoop::TYPE_UI, MessageLoop::current()->type());
+  
   RenderViewHost* render_view_host =
       RenderViewHost::FromID(render_process_id, render_view_id);
   if (!render_view_host)