Extract Favicon Download logic from FaviconTabHelper

chrome/browser/favicon/favicon_download_helper.cc

Index: chrome/browser/favicon/favicon_download_helper.cc
diff --git a/chrome/browser/favicon/favicon_download_helper.cc b/chrome/browser/favicon/favicon_download_helper.cc
new file mode 100644
index 0000000000000000000000000000000000000000..846fa36442247d989b7b2d9ca1f78ba741fbc3df
--- /dev/null
+++ b/chrome/browser/favicon/favicon_download_helper.cc
@@ -0,0 +1,50 @@
+// Copyright (c) 2012 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 "chrome/browser/favicon/favicon_download_helper.h"
+
+#include "chrome/browser/favicon/favicon_download_delegate.h"
+#include "chrome/browser/favicon/favicon_util.h"
+#include "chrome/common/icon_messages.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/browser/web_contents_delegate.h"
+
+using content::WebContents;
+
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(FaviconDownloadHelper)
+
+FaviconDownloadHelper::FaviconDownloadHelper(WebContents* web_contents)
+    : content::WebContentsObserver(web_contents),
+      external_delegate_(NULL) {
+}
+
+FaviconDownloadHelper::~FaviconDownloadHelper() {
+}
+
+int FaviconDownloadHelper::DownloadFavicon(const GURL& url, int image_size) {
+  content::RenderViewHost* host = web_contents()->GetRenderViewHost();
+  int id = FaviconUtil::DownloadFavicon(host, url, image_size);
+  return id;
+}
+
+bool FaviconDownloadHelper::OnMessageReceived(const IPC::Message& message) {
+  bool message_handled = false;   // Allow other handlers to receive these.
+  IPC_BEGIN_MESSAGE_MAP(FaviconDownloadHelper, message)
+    IPC_MESSAGE_HANDLER(IconHostMsg_DidDownloadFavicon, OnDidDownloadFavicon)
+    IPC_MESSAGE_UNHANDLED(message_handled = false)
+  IPC_END_MESSAGE_MAP()
+  return message_handled;
+}
+
+void FaviconDownloadHelper::OnDidDownloadFavicon(int id,
+                          const GURL& image_url,
+                          bool errored,
+                          int requested_size,
+                          const std::vector<SkBitmap>& bitmaps) {
+  if (external_delegate_) {
+    external_delegate_->OnDidDownloadFavicon(
+        id, image_url, errored, requested_size, bitmaps);
+  }
+}