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

content/browser/tab_contents/tab_contents_delegate.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/tab_contents/tab_contents_delegate.h"
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/memory/singleton.h"
 #include "content/browser/javascript_dialogs.h"
@@ skipping 109 matching lines @@
     TabContents* contents, bool blocked) {
 }
 
 void TabContentsDelegate::TabContentsFocused(TabContents* tab_content) {
 }
 
 int TabContentsDelegate::GetExtraRenderViewHeight() const {
   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;
 }
 
 bool TabContentsDelegate::ExecuteContextMenuCommand(int command) {
   return false;
 }
 
 void TabContentsDelegate::ShowPageInfo(Profile* profile,
                                        const GURL& url,
@@ skipping 134 matching lines @@
 
 void TabContentsDelegate::Attach(TabContents* tab_contents) {
   DCHECK(attached_contents_.find(tab_contents) == attached_contents_.end());
   attached_contents_.insert(tab_contents);
 }
 
 void TabContentsDelegate::Detach(TabContents* tab_contents) {
   DCHECK(attached_contents_.find(tab_contents) != attached_contents_.end());
   attached_contents_.erase(tab_contents);
 }