Move download stuff from download helper back to TabContents. This is basically a revert of r8576...

content/browser/tab_contents/tab_contents_delegate.cc

Index: content/browser/tab_contents/tab_contents_delegate.cc
===================================================================
--- content/browser/tab_contents/tab_contents_delegate.cc	(revision 92629)
+++ content/browser/tab_contents/tab_contents_delegate.cc	(working copy)
@@ -127,6 +127,14 @@
   return 0;
 }
 
+bool TabContentsDelegate::CanDownload(TabContents* source, int request_id) {
+  return true;
+}
+
+void TabContentsDelegate::OnStartDownload(TabContents* source,
+                                          DownloadItem* download) {
+}
+
 bool TabContentsDelegate::HandleContextMenu(const ContextMenuParams& params) {
   return false;
 }