Extract Favicon Download logic from FaviconTabHelper

chrome/browser/favicon/favicon_download_helper.cc

+// 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 "base/supports_user_data.h"
+#include "chrome/browser/favicon/favicon_download_helper_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;
+
+namespace {
+
+const char* kFaviconDownloadHelperWebContentsUserDataKey =
+    "web_contents_favicon_download";
+
+} // namespace
+
+// static
+void FaviconDownloadHelper::CreateForWebContentsAndDelegate(
+    content::WebContents* contents,
+    FaviconDownloadHelperDelegate* delegate) {
+  if (FromWebContents(contents))
+    return;
+
+  contents->SetUserData(kFaviconDownloadHelperWebContentsUserDataKey,
+                        new base::UserDataAdapter<FaviconDownloadHelper>(
+                            new FaviconDownloadHelper(contents, delegate)));
+}
+
+// static
+FaviconDownloadHelper* FaviconDownloadHelper::FromWebContents(
+    content::WebContents* contents) {
+  return base::UserDataAdapter<FaviconDownloadHelper>::Get(
+      contents, kFaviconDownloadHelperWebContentsUserDataKey);
+}
+
+
+FaviconDownloadHelper::FaviconDownloadHelper(
+    WebContents* web_contents,
+    FaviconDownloadHelperDelegate* delegate)
+    : content::WebContentsObserver(web_contents),
+      delegate_(delegate) {
+}
+
+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);

[joth, 2012/10/18 21:51:13]

internally this sends IconMsg_DownloadFavicon ipc which is handled by
chrome/renderer/chrome_render_view_observer.cc which we don't (or, won't) have
installed in webview, so some of the renderer side code also needs extracting I
think.


working back, this line adds a dependency on FaviconUtil which itself pulls in
chrome/browser/history... types. So I think we'll need to unpick those too.
(maybe, just remove DownloadFavicon from FaviconUtil and do it right here?)

[Cait (Slow), 2012/10/23 21:36:43]

CL extracting renderer-side code: http://codereview.chromium.org/11232068/
Unfortunately, there are a couple places in (mostly in ash) which call
FaviconUtil::DownloadFavicon directly, so I can't remove it just yet. Once this
CL has landed, I'll try to switch them over to using the
FaviconDownloadHelper/Delegate model (and move DownloadFavicon into the helper).

+  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 (delegate_) {
+    delegate_->OnDidDownloadFavicon(
+        id, image_url, errored, requested_size, bitmaps);
+  }
+}