move favicon download code from chrome/ into content/

-chrome/renderer/favicon_helper.(h|cc) ->content/renderer/...
-chrome/common/icon_messages.h -> content/common/icon_messages.h
-favicon_download_helper.(h|cc) API incorporated into web_contents 
-chrome/browser/favicon/favicon_download_helper_delegate.h -> content/public/browser/favicon_download_delegate.h

Depends on: 
https://codereview.chromium.org/11416179/
https://codereview.chromium.org/11421051/

BUG=160995

Review URL: https://chromiumcodereview.appspot.com/11411180

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@171411 0039d316-1c4b-4281-b951-d872f2087c98

47 files changed, 336 insertions, 463 deletions

diff --git a/chrome/browser/favicon/DEPS b/chrome/browser/favicon/DEPS
index 3460227..f261846 100644
--- a/chrome/browser/favicon/DEPS
+++ b/chrome/browser/favicon/DEPS
@@ -34,16 +34,6 @@
 
 specific_include_rules = {
   # TODO(caitkp): Look into removing history/ dependencies.
-  'favicon_download_helper(_delegate)*\.(h|cc)': [
-    "-chrome",
-    "-chrome/browser",
-    "+chrome/browser/favicon/favicon_download_helper.h",
-    "+chrome/browser/favicon/favicon_download_helper_delegate.h",
-    "+chrome/browser/favicon/favicon_util.h",
-    "+chrome/common/icon_messages.h",
-    "+chrome/common/favicon_url.h",
-  ],
-
   'favicon_util\.(h|cc)': [
     "-chrome",
     "-chrome/browser",
diff --git a/chrome/browser/favicon/favicon_download_helper.cc b/chrome/browser/favicon/favicon_download_helper.cc
deleted file mode 100644
index 2b364d6..0000000
--- a/chrome/browser/favicon/favicon_download_helper.cc
+++ /dev/null
@@ -1,79 +0,0 @@
-// 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_helper_delegate.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 {
-static int StartDownload(content::RenderViewHost* rvh,
-                           const GURL& url,
-                           int image_size) {
-  static int id = 0;
-  rvh->Send(new IconMsg_DownloadFavicon(rvh->GetRoutingID(), ++id, url,
-                                        image_size));
-  return id;
-}
-}  // namespace.
-
-FaviconDownloadHelper::FaviconDownloadHelper(
-    WebContents* web_contents,
-    FaviconDownloadHelperDelegate* delegate)
-    : content::WebContentsObserver(web_contents),
-      delegate_(delegate) {
-  DCHECK(delegate_);
-}
-
-FaviconDownloadHelper::~FaviconDownloadHelper() {
-}
-
-int FaviconDownloadHelper::DownloadFavicon(const GURL& url, int image_size) {
-  content::RenderViewHost* host = web_contents()->GetRenderViewHost();
-  int id = StartDownload(host, url, image_size);
-  DownloadIdList::iterator i =
-      std::find(download_ids_.begin(), download_ids_.end(), id);
-  DCHECK(i == download_ids_.end());
-  download_ids_.insert(id);
-  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_HANDLER(IconHostMsg_UpdateFaviconURL, OnUpdateFaviconURL)
-    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) {
-  DownloadIdList::iterator i =
-      std::find(download_ids_.begin(), download_ids_.end(), id);
-  if (i == download_ids_.end()) {
-    // Currently WebContents notifies us of ANY downloads so that it is
-    // possible to get here.
-    return;
-  }
-  delegate_->OnDidDownloadFavicon(
-      id, image_url, errored, requested_size, bitmaps);
-  download_ids_.erase(i);
-}
-
-void FaviconDownloadHelper::OnUpdateFaviconURL(
-    int32 page_id,
-    const std::vector<FaviconURL>& candidates) {
-  delegate_->OnUpdateFaviconURL(page_id, candidates);
-}
diff --git a/chrome/browser/favicon/favicon_download_helper.h b/chrome/browser/favicon/favicon_download_helper.h
deleted file mode 100644
index eb5c372..0000000
--- a/chrome/browser/favicon/favicon_download_helper.h
+++ /dev/null
@@ -1,75 +0,0 @@
-// 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.
-
-#ifndef CHROME_BROWSER_FAVICON_FAVICON_DOWNLOAD_HELPER_H_
-#define CHROME_BROWSER_FAVICON_FAVICON_DOWNLOAD_HELPER_H_
-
-#include <vector>
-
-#include "base/basictypes.h"
-#include "base/memory/ref_counted.h"
-#include "chrome/common/favicon_url.h"
-#include "content/public/browser/web_contents_observer.h"
-
-namespace content {
-class WebContents;
-}
-
-namespace gfx {
-class Image;
-}
-
-class GURL;
-class FaviconDownloadHelperDelegate;
-class SkBitmap;
-
-// FaviconDownloadHelper handles requests to download favicons, and listens for
-// the IPC messages from the renderer.
-class FaviconDownloadHelper : public content::WebContentsObserver {
- public:
-  FaviconDownloadHelper(content::WebContents* web_contents,
-                        FaviconDownloadHelperDelegate* delegate);
-
-  virtual ~FaviconDownloadHelper();
-
-  // Starts the download of the given favicon |url| and returns the unique id of
-  // the download request. When the download is finished, an
-  // IconHostMsg_DidDownloadFavicon IPC message will be sent and passed on to
-  // the delegate via FaviconDownloadHelperDelegate::OnDidDownloadFavicon().
-  // Note that |image_size| is a hint for images with multiple sizes. The
-  // downloaded image is not resized to the given image_size. If 0 is passed,
-  // the first frame of the image is returned.
-  int DownloadFavicon(const GURL& url, int image_size);
-
- protected:
-  // content::WebContentsObserver overrides.
-  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
-
- private:
-  typedef std::set<int> DownloadIdList;
-
-  // Message handler for IconHostMsg_DidDownloadFavicon. Called when the icon
-  // at |image_url| has been downloaded.
-  // |bitmaps| is a list of all the frames of the icon at |image_url|.
-  void OnDidDownloadFavicon(int id,
-                            const GURL& image_url,
-                            bool errored,
-                            int requested_size,
-                            const std::vector<SkBitmap>& bitmaps);
-
-  // Message Handler, called when the FaviconURL associated with the specified
-  // page is updated.
-  void OnUpdateFaviconURL(int32 page_id,
-                          const std::vector<FaviconURL>& candidates);
-
-  // Delegate to pass Favicon bitmaps back to. Weak.
-  FaviconDownloadHelperDelegate* delegate_;
-
-  // Ids of pending downloads.
-  DownloadIdList download_ids_;
-
-  DISALLOW_IMPLICIT_CONSTRUCTORS(FaviconDownloadHelper);
-};
-
-#endif  // CHROME_BROWSER_FAVICON_FAVICON_DOWNLOAD_HELPER_H_
diff --git a/chrome/browser/favicon/favicon_download_helper_delegate.h b/chrome/browser/favicon/favicon_download_helper_delegate.h
deleted file mode 100644
index ebdb5c2..0000000
--- a/chrome/browser/favicon/favicon_download_helper_delegate.h
+++ /dev/null
@@ -1,38 +0,0 @@
-// 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.
-
-#ifndef CHROME_BROWSER_FAVICON_FAVICON_DOWNLOAD_HELPER_DELEGATE_H_
-#define CHROME_BROWSER_FAVICON_FAVICON_DOWNLOAD_HELPER_DELEGATE_H_
-
-#include <vector>
-
-#include "base/basictypes.h"
-
-class GURL;
-class SkBitmap;
-struct FaviconURL;
-
-// This class provides a delegate interface for a FaviconDownloadHelper.  It
-// allows the FaviconDownloadHelper to pass favicon data back to its caller.
-class FaviconDownloadHelperDelegate {
- public:
-  // Called when the icon at |image_url| has been downloaded.
-  // |bitmaps| is a list of all the frames of the icon at |image_url|.
-  virtual void OnDidDownloadFavicon(
-      int id,
-      const GURL& image_url,
-      bool errored,
-      int requested_size,
-      const std::vector<SkBitmap>& bitmaps) {}
-
-  // Message Handler.
-  virtual void OnUpdateFaviconURL(
-      int32 page_id,
-      const std::vector<FaviconURL>& candidates) {}
-
- protected:
-  virtual ~FaviconDownloadHelperDelegate() {}
-};
-
-#endif  // CHROME_BROWSER_FAVICON_FAVICON_DOWNLOAD_HELPER_DELEGATE_H_
diff --git a/chrome/browser/favicon/favicon_handler.cc b/chrome/browser/favicon/favicon_handler.cc
index dfd7b70..78fd583 100644
--- a/chrome/browser/favicon/favicon_handler.cc
+++ b/chrome/browser/favicon/favicon_handler.cc
@@ -18,7 +18,6 @@
 #include "chrome/browser/favicon/favicon_util.h"
 #include "chrome/browser/history/select_favicon_frames.h"
 #include "chrome/browser/profiles/profile.h"
-#include "chrome/common/icon_messages.h"
 #include "content/public/browser/favicon_status.h"
 #include "content/public/browser/navigation_entry.h"
 #include "skia/ext/image_operations.h"
@@ -27,6 +26,7 @@
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/image/image_util.h"
 
+using content::FaviconURL;
 using content::NavigationEntry;
 
 namespace {
diff --git a/chrome/browser/favicon/favicon_handler.h b/chrome/browser/favicon/favicon_handler.h
index fb19d8f..7f2edee 100644
--- a/chrome/browser/favicon/favicon_handler.h
+++ b/chrome/browser/favicon/favicon_handler.h
@@ -13,8 +13,8 @@
 #include "chrome/browser/common/cancelable_request.h"
 #include "chrome/browser/favicon/favicon_service.h"
 #include "chrome/browser/favicon/favicon_tab_helper.h"
-#include "chrome/common/favicon_url.h"
 #include "chrome/common/ref_counted_util.h"
+#include "content/public/common/favicon_url.h"
 #include "googleurl/src/gurl.h"
 #include "ui/gfx/favicon_size.h"
 #include "ui/gfx/image/image.h"
@@ -94,7 +94,7 @@ class FaviconHandler {
   // Message Handler.  Must be public, because also called from
   // PrerenderContents. Collects the |image_urls| list.
   void OnUpdateFaviconURL(int32 page_id,
-                          const std::vector<FaviconURL>& candidates);
+                          const std::vector<content::FaviconURL>& candidates);
 
   // Processes the current image_irls_ entry, requesting the image from the
   // history / download service.
@@ -110,7 +110,9 @@ class FaviconHandler {
                             const std::vector<SkBitmap>& bitmaps);
 
   // For testing.
-  const std::deque<FaviconURL>& image_urls() const { return image_urls_; }
+  const std::deque<content::FaviconURL>& image_urls() const {
+    return image_urls_;
+  }
 
  protected:
   // These virtual methods make FaviconHandler testable and are overridden by
@@ -237,7 +239,7 @@ class FaviconHandler {
   void FetchFaviconInternal();
 
   // Return the current candidate if any.
-  FaviconURL* current_candidate() {
+  content::FaviconURL* current_candidate() {
     return (image_urls_.size() > 0) ? &image_urls_[0] : NULL;
   }
 
@@ -271,7 +273,7 @@ class FaviconHandler {
   const int icon_types_;
 
   // The prioritized favicon candidates from the page back from the renderer.
-  std::deque<FaviconURL> image_urls_;
+  std::deque<content::FaviconURL> image_urls_;
 
   // The FaviconBitmapResults from history.
   std::vector<history::FaviconBitmapResult> history_results_;
diff --git a/chrome/browser/favicon/favicon_handler_unittest.cc b/chrome/browser/favicon/favicon_handler_unittest.cc
index 55b9a22..4c29cef 100644
--- a/chrome/browser/favicon/favicon_handler_unittest.cc
+++ b/chrome/browser/favicon/favicon_handler_unittest.cc
@@ -6,9 +6,9 @@
 #include "chrome/browser/favicon/favicon_handler.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/test/base/chrome_render_view_host_test_harness.h"
+#include "content/public/browser/favicon_status.h"
 #include "content/public/browser/invalidate_type.h"
 #include "content/public/browser/navigation_entry.h"
-#include "content/public/browser/favicon_status.h"
 #include "content/public/browser/web_contents.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/gfx/codec/png_codec.h"
@@ -17,6 +17,7 @@
 
 class TestFaviconHandler;
 
+using content::FaviconURL;
 using content::NavigationEntry;
 using content::WebContents;
 
diff --git a/chrome/browser/favicon/favicon_tab_helper.cc b/chrome/browser/favicon/favicon_tab_helper.cc
index 912c636..8c9302c 100644
--- a/chrome/browser/favicon/favicon_tab_helper.cc
+++ b/chrome/browser/favicon/favicon_tab_helper.cc
@@ -4,7 +4,6 @@
 
 #include "chrome/browser/favicon/favicon_tab_helper.h"
 
-#include "chrome/browser/favicon/favicon_download_helper.h"
 #include "chrome/browser/favicon/favicon_handler.h"
 #include "chrome/browser/favicon/favicon_service_factory.h"
 #include "chrome/browser/favicon/favicon_util.h"
@@ -13,7 +12,6 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_notification_types.h"
-#include "chrome/common/icon_messages.h"
 #include "content/public/browser/favicon_status.h"
 #include "content/public/browser/invalidate_type.h"
 #include "content/public/browser/navigation_controller.h"
@@ -39,7 +37,6 @@ DEFINE_WEB_CONTENTS_USER_DATA_KEY(FaviconTabHelper)
 FaviconTabHelper::FaviconTabHelper(WebContents* web_contents)
     : content::WebContentsObserver(web_contents),
       profile_(Profile::FromBrowserContext(web_contents->GetBrowserContext())) {
-  favicon_download_helper_.reset(new FaviconDownloadHelper(web_contents, this));
   favicon_handler_.reset(new FaviconHandler(profile_, this,
                                             FaviconHandler::FAVICON));
   if (chrome::kEnableTouchIcon)
@@ -95,14 +92,6 @@ bool FaviconTabHelper::ShouldDisplayFavicon() {
   return true;
 }
 
-void FaviconTabHelper::OnUpdateFaviconURL(
-    int32 page_id,
-    const std::vector<FaviconURL>& candidates) {
-  favicon_handler_->OnUpdateFaviconURL(page_id, candidates);
-  if (touch_icon_handler_.get())
-    touch_icon_handler_->OnUpdateFaviconURL(page_id, candidates);
-}
-
 void FaviconTabHelper::SaveFavicon() {
   NavigationEntry* entry = web_contents()->GetController().GetActiveEntry();
   if (!entry || entry->GetURL().is_empty())
@@ -134,7 +123,9 @@ NavigationEntry* FaviconTabHelper::GetActiveEntry() {
 }
 
 int FaviconTabHelper::StartDownload(const GURL& url, int image_size) {
-  return favicon_download_helper_->DownloadFavicon(url, image_size);
+  return web_contents()->DownloadFavicon(url, image_size,
+      base::Bind(&FaviconTabHelper::DidDownloadFavicon,
+                 base::Unretained(this)));
 }
 
 void FaviconTabHelper::NotifyFaviconUpdated() {
@@ -164,7 +155,15 @@ void FaviconTabHelper::DidNavigateMainFrame(
   FetchFavicon(details.entry->GetURL());
 }
 
-void FaviconTabHelper::OnDidDownloadFavicon(
+void FaviconTabHelper::DidUpdateFaviconURL(
+    int32 page_id,
+    const std::vector<content::FaviconURL>& candidates) {
+  favicon_handler_->OnUpdateFaviconURL(page_id, candidates);
+  if (touch_icon_handler_.get())
+    touch_icon_handler_->OnUpdateFaviconURL(page_id, candidates);
+}
+
+void FaviconTabHelper::DidDownloadFavicon(
     int id,
     const GURL& image_url,
     bool errored,
diff --git a/chrome/browser/favicon/favicon_tab_helper.h b/chrome/browser/favicon/favicon_tab_helper.h
index 4dac687..261ab998 100644
--- a/chrome/browser/favicon/favicon_tab_helper.h
+++ b/chrome/browser/favicon/favicon_tab_helper.h
@@ -9,19 +9,17 @@
 
 #include "base/basictypes.h"
 #include "base/callback.h"
-#include "chrome/browser/favicon/favicon_download_helper_delegate.h"
 #include "chrome/browser/favicon/favicon_handler_delegate.h"
 #include "chrome/browser/history/history_types.h"
-#include "chrome/common/favicon_url.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
+#include "content/public/common/favicon_url.h"
 
 namespace gfx {
 class Image;
 }
 
 class GURL;
-class FaviconDownloadHelper;
 class FaviconHandler;
 class Profile;
 class SkBitmap;
@@ -34,7 +32,6 @@ class SkBitmap;
 //
 class FaviconTabHelper : public content::WebContentsObserver,
                          public FaviconHandlerDelegate,
-                         public FaviconDownloadHelperDelegate,
                          public content::WebContentsUserData<FaviconTabHelper> {
  public:
   virtual ~FaviconTabHelper();
@@ -55,11 +52,11 @@ class FaviconTabHelper : public content::WebContentsObserver,
   // space is provided for the favicon, and the favicon is never displayed.
   virtual bool ShouldDisplayFavicon();
 
-  // Message Handler.  Must be public, because also called from
-  // PrerenderContents.
-  virtual void OnUpdateFaviconURL(
+  // content::WebContentsObserver override. Must be public, because also
+  // called from PrerenderContents.
+  virtual void DidUpdateFaviconURL(
       int32 page_id,
-      const std::vector<FaviconURL>& candidates) OVERRIDE;
+      const std::vector<content::FaviconURL>& candidates) OVERRIDE;
 
   // Saves the favicon for the current page.
   void SaveFavicon();
@@ -81,18 +78,16 @@ class FaviconTabHelper : public content::WebContentsObserver,
       const content::LoadCommittedDetails& details,
       const content::FrameNavigateParams& params) OVERRIDE;
 
-  // FaviconDownloadHelperDelegate overrides.
-  virtual void OnDidDownloadFavicon(
+  // Favicon download callback.
+  void DidDownloadFavicon(
       int id,
       const GURL& image_url,
       bool errored,
       int requested_size,
-      const std::vector<SkBitmap>& bitmaps) OVERRIDE;
+      const std::vector<SkBitmap>& bitmaps);
 
   Profile* profile_;
 
-  scoped_ptr<FaviconDownloadHelper> favicon_download_helper_;
-
   scoped_ptr<FaviconHandler> favicon_handler_;
 
   // Handles downloading touchicons. It is NULL if
diff --git a/chrome/browser/favicon/favicon_util.cc b/chrome/browser/favicon/favicon_util.cc
index 630f2b3..02c7326 100644
--- a/chrome/browser/favicon/favicon_util.cc
+++ b/chrome/browser/favicon/favicon_util.cc
@@ -6,7 +6,6 @@
 
 #include "chrome/browser/history/history_types.h"
 #include "chrome/browser/history/select_favicon_frames.h"
-#include "chrome/common/icon_messages.h"
 #include "content/public/browser/render_view_host.h"
 #include "googleurl/src/gurl.h"
 #include "ui/gfx/codec/png_codec.h"
diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index 3b38659..54cfdb1 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -20,7 +20,6 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/tab_contents/tab_contents.h"
 #include "chrome/common/chrome_notification_types.h"
-#include "chrome/common/icon_messages.h"
 #include "chrome/common/prerender_messages.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/browser_child_process_host.h"
@@ -32,6 +31,7 @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_view.h"
+#include "content/public/common/favicon_url.h"
 #include "ui/gfx/rect.h"
 
 using content::DownloadItem;
@@ -295,7 +295,6 @@ void PrerenderContents::StartPrerendering(
 
   tab_contents_delegate_.reset(new TabContentsDelegateImpl(this));
   new_contents->SetDelegate(tab_contents_delegate_.get());
-
   // Set the size of the prerender WebContents.
   prerender_contents_->web_contents()->GetView()->SizeContents(size_);
 
@@ -484,13 +483,13 @@ WebContents* PrerenderContents::CreateWebContents(
       profile_, NULL, MSG_ROUTING_NONE, NULL, session_storage_namespace_map);
 }
 
-void PrerenderContents::OnUpdateFaviconURL(
+void PrerenderContents::DidUpdateFaviconURL(
     int32 page_id,
-    const std::vector<FaviconURL>& urls) {
+    const std::vector<content::FaviconURL>& urls) {
   VLOG(1) << "PrerenderContents::OnUpdateFaviconURL" << icon_url_;
-  for (std::vector<FaviconURL>::const_iterator it = urls.begin();
+  for (std::vector<content::FaviconURL>::const_iterator it = urls.begin();
        it != urls.end(); ++it) {
-    if (it->icon_type == FaviconURL::FAVICON) {
+    if (it->icon_type == content::FaviconURL::FAVICON) {
       icon_url_ = it->icon_url;
       VLOG(1) << icon_url_;
       return;
diff --git a/chrome/browser/prerender/prerender_contents.h b/chrome/browser/prerender/prerender_contents.h
index 7461937..8db24c7 100644
--- a/chrome/browser/prerender/prerender_contents.h
+++ b/chrome/browser/prerender/prerender_contents.h
@@ -24,13 +24,13 @@
 
 class Profile;
 class TabContents;
-struct FaviconURL;
 
 namespace base {
 class ProcessMetrics;
 }
 
 namespace content {
+struct FaviconURL;
 class RenderViewHost;
 class SessionStorageNamespace;
 class WebContents;
@@ -202,6 +202,8 @@ class PrerenderContents : public content::NotificationObserver,
       const GURL& validated_url,
       bool is_main_frame,
       content::RenderViewHost* render_view_host) OVERRIDE;
+  virtual void DidUpdateFaviconURL(int32 page_id,
+      const std::vector<content::FaviconURL>& urls) OVERRIDE;
 
   virtual void RenderViewGone(base::TerminationStatus status) OVERRIDE;
 
@@ -294,9 +296,6 @@ class PrerenderContents : public content::NotificationObserver,
 
   friend class PrerenderRenderViewHostObserver;
 
-  // Message handlers.
-  void OnUpdateFaviconURL(int32 page_id, const std::vector<FaviconURL>& urls);
-
   // Returns the RenderViewHost Delegate for this prerender.
   content::WebContents* GetWebContents();
 
diff --git a/chrome/browser/prerender/prerender_manager.cc b/chrome/browser/prerender/prerender_manager.cc
index 1cab97e..8dbbf53 100644
--- a/chrome/browser/prerender/prerender_manager.cc
+++ b/chrome/browser/prerender/prerender_manager.cc
@@ -54,6 +54,7 @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_view.h"
+#include "content/public/common/favicon_url.h"
 
 using content::BrowserThread;
 using content::RenderViewHost;
@@ -451,10 +452,10 @@ bool PrerenderManager::MaybeUsePrerenderedPage(WebContents* web_contents,
 
   GURL icon_url = prerender_contents->icon_url();
   if (!icon_url.is_empty()) {
-    std::vector<FaviconURL> urls;
-    urls.push_back(FaviconURL(icon_url, FaviconURL::FAVICON));
+    std::vector<content::FaviconURL> urls;
+    urls.push_back(content::FaviconURL(icon_url, content::FaviconURL::FAVICON));
     FaviconTabHelper::FromWebContents(new_tab_contents->web_contents())->
-        OnUpdateFaviconURL(prerender_contents->page_id(), urls);
+        DidUpdateFaviconURL(prerender_contents->page_id(), urls);
   }
 
   // Update PPLT metrics:
diff --git a/chrome/browser/prerender/prerender_render_view_host_observer.cc b/chrome/browser/prerender/prerender_render_view_host_observer.cc
index fdc6342..7317b61 100644
--- a/chrome/browser/prerender/prerender_render_view_host_observer.cc
+++ b/chrome/browser/prerender/prerender_render_view_host_observer.cc
@@ -5,7 +5,6 @@
 #include "chrome/browser/prerender/prerender_render_view_host_observer.h"
 
 #include "chrome/browser/prerender/prerender_contents.h"
-#include "chrome/common/icon_messages.h"
 #include "chrome/common/render_messages.h"
 
 using content::RenderViewHost;
@@ -34,7 +33,6 @@ bool PrerenderRenderViewHostObserver::OnMessageReceived(
   bool handled = true;
   // The following messages we do want to consume.
   IPC_BEGIN_MESSAGE_MAP(PrerenderRenderViewHostObserver, message)
-    IPC_MESSAGE_HANDLER(IconHostMsg_UpdateFaviconURL, OnUpdateFaviconURL)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_MaybeCancelPrerenderForHTML5Media,
                         OnMaybeCancelPrerenderForHTML5Media)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_CancelPrerenderForPrinting,
@@ -55,12 +53,6 @@ bool PrerenderRenderViewHostObserver::Send(IPC::Message* message) {
   return content::RenderViewHostObserver::Send(message);
 }
 
-void PrerenderRenderViewHostObserver::OnUpdateFaviconURL(
-    int32 page_id,
-    const std::vector<FaviconURL>& urls) {
-  prerender_contents_->OnUpdateFaviconURL(page_id, urls);
-}
-
 void PrerenderRenderViewHostObserver::OnMaybeCancelPrerenderForHTML5Media() {
   prerender_contents_->Destroy(FINAL_STATUS_HTML5_MEDIA);
 }
diff --git a/chrome/browser/prerender/prerender_render_view_host_observer.h b/chrome/browser/prerender/prerender_render_view_host_observer.h
index e6ecf8e..c804b86 100644
--- a/chrome/browser/prerender/prerender_render_view_host_observer.h
+++ b/chrome/browser/prerender/prerender_render_view_host_observer.h
@@ -9,9 +9,8 @@
 
 #include "content/public/browser/render_view_host_observer.h"
 
-struct FaviconURL;
-
 namespace content {
+struct FaviconURL;
 class RenderViewHost;
 }
 
@@ -40,7 +39,7 @@ class PrerenderRenderViewHostObserver : public content::RenderViewHostObserver {
 
  private:
   // Message handlers.
-  void OnUpdateFaviconURL(int32 page_id, const std::vector<FaviconURL>& urls);
+
   void OnMaybeCancelPrerenderForHTML5Media();
   void OnCancelPrerenderForPrinting();
 
diff --git a/chrome/browser/ui/ash/launcher/launcher_favicon_loader.cc b/chrome/browser/ui/ash/launcher/launcher_favicon_loader.cc
index 468d7da..1969041 100644
--- a/chrome/browser/ui/ash/launcher/launcher_favicon_loader.cc
+++ b/chrome/browser/ui/ash/launcher/launcher_favicon_loader.cc
@@ -5,14 +5,11 @@
 #include "chrome/browser/ui/ash/launcher/launcher_favicon_loader.h"
 
 #include "base/logging.h"
-#include "chrome/browser/favicon/favicon_download_helper.h"
-#include "chrome/browser/favicon/favicon_download_helper_delegate.h"
+#include "base/memory/weak_ptr.h"
 #include "chrome/browser/ui/ash/launcher/browser_launcher_item_controller.h"
-#include "chrome/common/favicon_url.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"
+#include "content/public/browser/web_contents_observer.h"
 #include "googleurl/src/gurl.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 
@@ -26,12 +23,14 @@ const int kMaxBitmapSize = 256;
 // These icon bitmaps are not resized and are not cached beyond the lifetime
 // of the class. Bitmaps larger than kMaxBitmapSize are ignored.
 
-class FaviconBitmapHandler : public FaviconDownloadHelperDelegate {
+class FaviconBitmapHandler : public content::WebContentsObserver {
  public:
   FaviconBitmapHandler(content::WebContents* web_contents,
                        LauncherFaviconLoader::Delegate* delegate)
-      : delegate_(delegate) {
-    download_helper_.reset(new FaviconDownloadHelper(web_contents, this));
+      : content::WebContentsObserver(web_contents),
+        delegate_(delegate),
+        web_contents_(web_contents),
+        ALLOW_THIS_IN_INITIALIZER_LIST(weak_ptr_factory_(this)) {
   }
 
   ~FaviconBitmapHandler() {}
@@ -40,25 +39,24 @@ class FaviconBitmapHandler : public FaviconDownloadHelperDelegate {
 
   bool HasPendingDownloads() const;
 
-  // FaviconDownloadHelperDelegate methods
-  virtual void OnUpdateFaviconURL(
+  // content::WebContentObserver implementation.
+  virtual void DidUpdateFaviconURL(
     int32 page_id,
-    const std::vector<FaviconURL>& candidates) OVERRIDE;
-
-  virtual void OnDidDownloadFavicon(
-    int id,
-    const GURL& image_url,
-    bool errored,
-    int requested_size,
-    const std::vector<SkBitmap>& bitmaps) OVERRIDE;
+    const std::vector<content::FaviconURL>& candidates) OVERRIDE;
 
  private:
-  void DownloadFavicon(const GURL& image_url);
+  void DidDownloadFavicon(
+      int id,
+      const GURL& image_url,
+      bool errored,
+      int requested_size,
+      const std::vector<SkBitmap>& bitmaps);
+
   void AddFavicon(const GURL& image_url, const SkBitmap& new_bitmap);
 
   LauncherFaviconLoader::Delegate* delegate_;
 
-  scoped_ptr<FaviconDownloadHelper> download_helper_;
+  content::WebContents* web_contents_;
 
   typedef std::set<GURL> UrlSet;
   // Map of pending download urls.
@@ -69,12 +67,14 @@ class FaviconBitmapHandler : public FaviconDownloadHelperDelegate {
   SkBitmap bitmap_;
   GURL bitmap_url_;
 
+  base::WeakPtrFactory<FaviconBitmapHandler> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(FaviconBitmapHandler);
 };
 
-void FaviconBitmapHandler::OnUpdateFaviconURL(
+void FaviconBitmapHandler::DidUpdateFaviconURL(
     int32 page_id,
-    const std::vector<FaviconURL>& candidates) {
+    const std::vector<content::FaviconURL>& candidates) {
   // This function receives a complete list of faviocn urls for the page.
   // It may get called multiple times with the same list, and will also get
   // called any time an item is added or removed. As such, we track processed
@@ -82,9 +82,9 @@ void FaviconBitmapHandler::OnUpdateFaviconURL(
   UrlSet new_pending, new_processed;
   // Create a map of valid favicon urls.
   std::set<GURL> urls;
-  for (std::vector<FaviconURL>::const_iterator iter = candidates.begin();
-       iter != candidates.end(); ++iter) {
-    if (iter->icon_type != FaviconURL::FAVICON)
+  std::vector<content::FaviconURL>::const_iterator iter;
+  for (iter = candidates.begin(); iter != candidates.end(); ++iter) {
+    if (iter->icon_type != content::FaviconURL::FAVICON)
       continue;
     const GURL& url = iter->icon_url;
     if (url.is_valid())
@@ -110,11 +110,17 @@ void FaviconBitmapHandler::OnUpdateFaviconURL(
     if (pending_requests_.find(*iter) != pending_requests_.end())
       continue;  // Skip already pending downloads.
     pending_requests_.insert(*iter);
-    download_helper_->DownloadFavicon(*iter, 0);
+    web_contents_->DownloadFavicon(*iter, 0,
+        base::Bind(&FaviconBitmapHandler::DidDownloadFavicon,
+                   weak_ptr_factory_.GetWeakPtr()));
   }
 }
 
-void FaviconBitmapHandler::OnDidDownloadFavicon(
+bool FaviconBitmapHandler::HasPendingDownloads() const {
+  return !pending_requests_.empty();
+}
+
+void FaviconBitmapHandler::DidDownloadFavicon(
     int id,
     const GURL& image_url,
     bool errored,
@@ -132,10 +138,6 @@ void FaviconBitmapHandler::OnDidDownloadFavicon(
     AddFavicon(image_url, bitmaps[0]);
 }
 
-bool FaviconBitmapHandler::HasPendingDownloads() const {
-  return !pending_requests_.empty();
-}
-
 void FaviconBitmapHandler::AddFavicon(const GURL& image_url,
                                       const SkBitmap& new_bitmap) {
   processed_requests_.insert(image_url);
diff --git a/chrome/browser/ui/ash/launcher/launcher_favicon_loader.h b/chrome/browser/ui/ash/launcher/launcher_favicon_loader.h
index 2fd0302..6327c02 100644
--- a/chrome/browser/ui/ash/launcher/launcher_favicon_loader.h
+++ b/chrome/browser/ui/ash/launcher/launcher_favicon_loader.h
@@ -9,7 +9,7 @@
 
 #include "base/basictypes.h"
 #include "base/callback.h"
-#include "chrome/common/favicon_url.h"
+#include "content/public/common/favicon_url.h"
 
 class GURL;
 class SkBitmap;
diff --git a/chrome/browser/ui/ash/launcher/launcher_favicon_loader_browsertest.cc b/chrome/browser/ui/ash/launcher/launcher_favicon_loader_browsertest.cc
index cd1173c..c06e2ab 100644
--- a/chrome/browser/ui/ash/launcher/launcher_favicon_loader_browsertest.cc
+++ b/chrome/browser/ui/ash/launcher/launcher_favicon_loader_browsertest.cc
@@ -5,19 +5,19 @@
 #include <vector>
 
 #include "base/file_path.h"
+#include "base/stringprintf.h"
 #include "base/time.h"
 #include "chrome/browser/ui/ash/launcher/browser_launcher_item_controller.h"
 #include "chrome/browser/ui/ash/launcher/launcher_favicon_loader.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/views/frame/browser_view.h"
-#include "chrome/common/favicon_url.h"
-#include "chrome/common/icon_messages.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_observer.h"
+#include "content/public/common/favicon_url.h"
 #include "net/test/test_server.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -39,22 +39,13 @@ class ContentsObserver : public content::WebContentsObserver {
   }
 
   // content::WebContentsObserver overrides.
-  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE {
-    bool message_handled = false;   // Allow other handlers to receive these.
-    IPC_BEGIN_MESSAGE_MAP(ContentsObserver, message)
-      IPC_MESSAGE_HANDLER(IconHostMsg_UpdateFaviconURL, OnUpdateFaviconURL)
-      IPC_MESSAGE_UNHANDLED(message_handled = false)
-    IPC_END_MESSAGE_MAP()
-    return message_handled;
-  }
-
- private:
-  void OnUpdateFaviconURL(int32 page_id,
-                          const std::vector<FaviconURL>& candidates) {
+  virtual void DidUpdateFaviconURL(int32 page_id,
+      const std::vector<content::FaviconURL>& candidates) OVERRIDE {
     if (!candidates.empty())
       got_favicons_ = true;
   }
 
+ private:
   bool got_favicons_;
 };
 
diff --git a/chrome/browser/ui/metro_pin_tab_helper_win.cc b/chrome/browser/ui/metro_pin_tab_helper_win.cc
index 195b8cc..5d5c22a 100644
--- a/chrome/browser/ui/metro_pin_tab_helper_win.cc
+++ b/chrome/browser/ui/metro_pin_tab_helper_win.cc
@@ -18,12 +18,10 @@
 #include "base/string_number_conversions.h"
 #include "base/utf_string_conversions.h"
 #include "base/win/metro.h"
-#include "chrome/browser/favicon/favicon_download_helper.h"
 #include "chrome/browser/favicon/favicon_tab_helper.h"
 #include "chrome/browser/favicon/favicon_util.h"
 #include "chrome/browser/ui/tab_contents/tab_contents.h"
 #include "chrome/common/chrome_paths.h"
-#include "chrome/common/icon_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_contents.h"
 #include "crypto/sha2.h"
@@ -368,9 +366,7 @@ void MetroPinTabHelper::FaviconChooser::AddPendingRequest(int request_id) {
 }
 
 MetroPinTabHelper::MetroPinTabHelper(content::WebContents* web_contents)
-    : content::WebContentsObserver(web_contents),
-      ALLOW_THIS_IN_INITIALIZER_LIST(
-          favicon_download_helper_(web_contents, this)) {
+    : content::WebContentsObserver(web_contents) {
 }
 
 MetroPinTabHelper::~MetroPinTabHelper() {}
@@ -425,12 +421,14 @@ void MetroPinTabHelper::TogglePinnedToStartScreen() {
 
   // Request all the candidates.
   int image_size = 0; // Request the full sized image.
-  for (std::vector<FaviconURL>::const_iterator iter =
+  for (std::vector<content::FaviconURL>::const_iterator iter =
            favicon_url_candidates_.begin();
        iter != favicon_url_candidates_.end();
        ++iter) {
     favicon_chooser_->AddPendingRequest(
-        favicon_download_helper_.DownloadFavicon(iter->icon_url, image_size));
+        web_contents()->DownloadFavicon(iter->icon_url, image_size,
+            base::Bind(&MetroPinTabHelper::DidDownloadFavicon,
+                       base::Unretained(this))));
   }
 
 }
@@ -446,13 +444,13 @@ void MetroPinTabHelper::DidNavigateMainFrame(
   favicon_url_candidates_.clear();
 }
 
-void MetroPinTabHelper::OnUpdateFaviconURL(
+void MetroPinTabHelper::DidUpdateFaviconURL(
     int32 page_id,
-    const std::vector<FaviconURL>& candidates) {
+    const std::vector<content::FaviconURL>& candidates) {
   favicon_url_candidates_ = candidates;
 }
 
-void MetroPinTabHelper::OnDidDownloadFavicon(
+void MetroPinTabHelper::DidDownloadFavicon(
     int id,
     const GURL& image_url,
     bool errored,
diff --git a/chrome/browser/ui/metro_pin_tab_helper_win.h b/chrome/browser/ui/metro_pin_tab_helper_win.h
index 45b1573..63770ce 100644
--- a/chrome/browser/ui/metro_pin_tab_helper_win.h
+++ b/chrome/browser/ui/metro_pin_tab_helper_win.h
@@ -7,19 +7,16 @@
 
 #include <vector>
 
-#include "chrome/browser/favicon/favicon_download_helper.h"
-#include "chrome/browser/favicon/favicon_download_helper_delegate.h"
-#include "chrome/common/favicon_url.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
+#include "content/public/common/favicon_url.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/gfx/image/image_skia.h"
 
 // Per-tab class to help manage metro pinning.
 class MetroPinTabHelper
     : public content::WebContentsObserver,
-      public content::WebContentsUserData<MetroPinTabHelper>,
-      public FaviconDownloadHelperDelegate {
+      public content::WebContentsUserData<MetroPinTabHelper> {
  public:
   virtual ~MetroPinTabHelper();
 
@@ -31,6 +28,9 @@ class MetroPinTabHelper
   virtual void DidNavigateMainFrame(
       const content::LoadCommittedDetails& details,
       const content::FrameNavigateParams& params) OVERRIDE;
+  virtual void DidUpdateFaviconURL(
+      int32 page_id,
+      const std::vector<content::FaviconURL>& candidates) OVERRIDE;
 
  private:
   // The FaviconDownloader class handles downloading the favicons when a page
@@ -41,29 +41,24 @@ class MetroPinTabHelper
   explicit MetroPinTabHelper(content::WebContents* tab_contents);
   friend class content::WebContentsUserData<MetroPinTabHelper>;
 
-  // FaviconDownloadHelperDelegate overrides.
-  void OnUpdateFaviconURL(int32 page_id,
-                          const std::vector<FaviconURL>& candidates) OVERRIDE;
-
-  void OnDidDownloadFavicon(int id,
-                            const GURL& image_url,
-                            bool errored,
-                            int requested_size,
-                            const std::vector<SkBitmap>& bitmaps) OVERRIDE;
+  // Favicon download callback.
+  void DidDownloadFavicon(int id,
+                          const GURL& image_url,
+                          bool errored,
+                          int requested_size,
+                          const std::vector<SkBitmap>& bitmaps);
 
   void UnPinPageFromStartScreen();
 
-  // Called by the |favicon_downloader_| when it has finished.
+  // Called by the |favicon_chooser_| when it has finished.
   void FaviconDownloaderFinished();
 
   // Candidate Favicon URLs for the current page.
-  std::vector<FaviconURL> favicon_url_candidates_;
+  std::vector<content::FaviconURL> favicon_url_candidates_;
 
   // The currently active FaviconChooser, if there is one.
   scoped_ptr<FaviconChooser> favicon_chooser_;
 
-  // FaviconDownloadHelper handles the sending and listening for IPC messages.
-  FaviconDownloadHelper favicon_download_helper_;
 
   DISALLOW_COPY_AND_ASSIGN(MetroPinTabHelper);
 };
diff --git a/chrome/browser/ui/views/ash/balloon_view_ash.cc b/chrome/browser/ui/views/ash/balloon_view_ash.cc
index 0e3d242..c0ea83f 100644
--- a/chrome/browser/ui/views/ash/balloon_view_ash.cc
+++ b/chrome/browser/ui/views/ash/balloon_view_ash.cc
@@ -9,12 +9,10 @@
 #include "base/logging.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/extension_service.h"
-#include "chrome/browser/favicon/favicon_download_helper.h"
 #include "chrome/browser/favicon/favicon_util.h"
 #include "chrome/browser/notifications/balloon_collection.h"
 #include "chrome/browser/notifications/notification.h"
 #include "chrome/browser/profiles/profile.h"
-#include "chrome/common/icon_messages.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/site_instance.h"
@@ -39,7 +37,8 @@ message_center::MessageCenter* GetMessageCenter() {
 
 BalloonViewAsh::BalloonViewAsh(BalloonCollection* collection)
     : collection_(collection),
-      balloon_(NULL) {
+      balloon_(NULL),
+      ALLOW_THIS_IN_INITIALIZER_LIST(weak_ptr_factory_(this)) {
 }
 
 BalloonViewAsh::~BalloonViewAsh() {
@@ -90,6 +89,20 @@ BalloonHost* BalloonViewAsh::GetHost() const {
   return NULL;
 }
 
+void BalloonViewAsh::DidDownloadFavicon(
+    int id,
+    const GURL& image_url,
+    bool errored,
+    int requested_size,
+    const std::vector<SkBitmap>& bitmaps) {
+  if (id != current_download_id_ || bitmaps.empty())
+    return;
+  GetMessageCenter()->SetNotificationImage(
+      cached_notification_id_, gfx::ImageSkia(bitmaps[0]));
+  current_download_id_ = -1;
+  cached_notification_id_.clear();
+}
+
 void BalloonViewAsh::FetchIcon(const Notification& notification) {
   if (!notification.icon().isNull()) {
     GetMessageCenter()->SetNotificationImage(
@@ -109,26 +122,13 @@ void BalloonViewAsh::FetchIcon(const Notification& notification) {
     LOG(WARNING) << "Notification has icon url but no WebContents";
     return;
   }
-  icon_fetcher_.reset(new FaviconDownloadHelper(web_contents, this));
-  current_download_id_ = icon_fetcher_->DownloadFavicon(
-      notification.icon_url(), kNotificationIconImageSize);
+  current_download_id_ = web_contents->DownloadFavicon(
+      notification.icon_url(), kNotificationIconImageSize,
+      base::Bind(&BalloonViewAsh::DidDownloadFavicon,
+                 weak_ptr_factory_.GetWeakPtr()));
   cached_notification_id_ = notification.notification_id();
 }
 
-void BalloonViewAsh::OnDidDownloadFavicon(
-    int id,
-    const GURL& image_url,
-    bool errored,
-    int requested_size,
-    const std::vector<SkBitmap>& bitmaps) {
-  if (id != current_download_id_ || bitmaps.empty())
-    return;
-  GetMessageCenter()->SetNotificationImage(
-      cached_notification_id_, gfx::ImageSkia(bitmaps[0]));
-  current_download_id_ = -1;
-  cached_notification_id_.clear();
-}
-
 std::string BalloonViewAsh::GetExtensionId(Balloon* balloon) {
   ExtensionService* extension_service =
       balloon_->profile()->GetExtensionService();
diff --git a/chrome/browser/ui/views/ash/balloon_view_ash.h b/chrome/browser/ui/views/ash/balloon_view_ash.h
index ff56d34..097a93c 100644
--- a/chrome/browser/ui/views/ash/balloon_view_ash.h
+++ b/chrome/browser/ui/views/ash/balloon_view_ash.h
@@ -5,16 +5,16 @@
 #ifndef CHROME_BROWSER_UI_VIEWS_ASH_BALLOON_VIEW_ASH_H_
 #define CHROME_BROWSER_UI_VIEWS_ASH_BALLOON_VIEW_ASH_H_
 
-#include <map>
+#include <vector>
 
-#include "chrome/browser/favicon/favicon_download_helper_delegate.h"
+#include "base/memory/weak_ptr.h"
 #include "chrome/browser/notifications/balloon.h"
 
-class FaviconDownloadHelper;
+class GURL;
+class SkBitmap;
 
 // On Ash, a "BalloonView" is just a wrapper for ash notification entries.
-class BalloonViewAsh : public BalloonView,
-                       public FaviconDownloadHelperDelegate {
+class BalloonViewAsh : public BalloonView {
  public:
   explicit BalloonViewAsh(BalloonCollection* collection);
   virtual ~BalloonViewAsh();
@@ -27,27 +27,26 @@ class BalloonViewAsh : public BalloonView,
   virtual gfx::Size GetSize() const OVERRIDE;
   virtual BalloonHost* GetHost() const OVERRIDE;
 
-  // FaviconDownloadHelperDelegate interface:
-  virtual void OnDidDownloadFavicon(
+ private:
+  // Favicon download callback.
+  void DidDownloadFavicon(
       int id,
       const GURL& image_url,
       bool errored,
       int requested_size,
-      const std::vector<SkBitmap>& bitmaps) OVERRIDE;
-
- private:
+      const std::vector<SkBitmap>& bitmaps);
   void FetchIcon(const Notification& notification);
   std::string GetExtensionId(Balloon* balloon);
 
   BalloonCollection* collection_;
   Balloon* balloon_;
-  scoped_ptr<FaviconDownloadHelper> icon_fetcher_;
 
   // Track the current notification id and download id so that it can be updated
   // properly.
   int current_download_id_;
   std::string current_notification_id_;
   std::string cached_notification_id_;
+  base::WeakPtrFactory<BalloonViewAsh> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BalloonViewAsh);
 };
diff --git a/chrome/browser/ui/views/create_application_shortcut_view.cc b/chrome/browser/ui/views/create_application_shortcut_view.cc
index 6b63f21..df9eb50 100644
--- a/chrome/browser/ui/views/create_application_shortcut_view.cc
+++ b/chrome/browser/ui/views/create_application_shortcut_view.cc
@@ -11,7 +11,6 @@
 #include "base/utf_string_conversions.h"
 #include "base/win/windows_version.h"
 #include "chrome/browser/extensions/tab_helper.h"
-#include "chrome/browser/favicon/favicon_download_helper.h"
 #include "chrome/browser/favicon/favicon_util.h"
 #include "chrome/browser/history/select_favicon_frames.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -28,7 +27,7 @@
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/web_contents.h"
-#include "content/public/browser/web_contents_delegate.h"
+#include "googleurl/src/gurl.h"
 #include "grit/generated_resources.h"
 #include "grit/locale_settings.h"
 #include "grit/theme_resources.h"
@@ -445,18 +444,17 @@ void CreateUrlApplicationShortcutView::FetchIcon() {
   if (unprocessed_icons_.empty())  // No icons to fetch.
     return;
 
-  if (!download_helper_.get())
-    download_helper_.reset(new FaviconDownloadHelper(web_contents_, this));
-
-  pending_download_id_ = download_helper_->DownloadFavicon(
+  pending_download_id_ = web_contents_->DownloadFavicon(
       unprocessed_icons_.back().url,
       std::max(unprocessed_icons_.back().width,
-               unprocessed_icons_.back().height));
+               unprocessed_icons_.back().height),
+      base::Bind(&CreateUrlApplicationShortcutView::DidDownloadFavicon,
+                 base::Unretained(this)));
 
   unprocessed_icons_.pop_back();
 }
 
-void CreateUrlApplicationShortcutView::OnDidDownloadFavicon(
+void CreateUrlApplicationShortcutView::DidDownloadFavicon(
     int id,
     const GURL& image_url,
     bool errored,
diff --git a/chrome/browser/ui/views/create_application_shortcut_view.h b/chrome/browser/ui/views/create_application_shortcut_view.h
index db41f63..d2eeddb 100644
--- a/chrome/browser/ui/views/create_application_shortcut_view.h
+++ b/chrome/browser/ui/views/create_application_shortcut_view.h
@@ -11,12 +11,12 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "chrome/browser/extensions/image_loading_tracker.h"
-#include "chrome/browser/favicon/favicon_download_helper_delegate.h"
 #include "chrome/browser/web_applications/web_app.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/window/dialog_delegate.h"
 
 class FaviconDownloadHelper;
+class GURL;
 class Profile;
 class SkBitmap;
 
@@ -85,8 +85,7 @@ class CreateApplicationShortcutView : public views::DialogDelegateView,
 };
 
 // Create an application shortcut pointing to a URL.
-class CreateUrlApplicationShortcutView : public CreateApplicationShortcutView,
-                                         public FaviconDownloadHelperDelegate {
+class CreateUrlApplicationShortcutView : public CreateApplicationShortcutView {
  public:
   explicit CreateUrlApplicationShortcutView(content::WebContents* web_contents);
   virtual ~CreateUrlApplicationShortcutView();
@@ -98,20 +97,17 @@ class CreateUrlApplicationShortcutView : public CreateApplicationShortcutView,
   // The first largest icon downloaded and decoded successfully will be used.
   void FetchIcon();
 
-  // FaviconDownloadHelperDelegate overrides.
-  virtual void OnDidDownloadFavicon(
+  // Favicon download callback.
+  void DidDownloadFavicon(
       int id,
       const GURL& image_url,
       bool errored,
       int requested_size,
-      const std::vector<SkBitmap>& bitmaps) OVERRIDE;
+      const std::vector<SkBitmap>& bitmaps);
 
   // The tab whose URL is being turned into an app.
   content::WebContents* web_contents_;
 
-  // Helper class to manage the downloading of favicons.
-  scoped_ptr<FaviconDownloadHelper> download_helper_;
-
   // Pending app icon download tracked by us.
   int pending_download_id_;
 
diff --git a/chrome/browser/ui/web_applications/web_app_ui.cc b/chrome/browser/ui/web_applications/web_app_ui.cc
index a7f9b98..abfd9b4 100644
--- a/chrome/browser/ui/web_applications/web_app_ui.cc
+++ b/chrome/browser/ui/web_applications/web_app_ui.cc
@@ -11,8 +11,6 @@
 #include "base/string16.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/tab_helper.h"
-#include "chrome/browser/favicon/favicon_download_helper.h"
-#include "chrome/browser/favicon/favicon_download_helper_delegate.h"
 #include "chrome/browser/favicon/favicon_tab_helper.h"
 #include "chrome/browser/favicon/favicon_util.h"
 #include "chrome/browser/profiles/profile.h"
@@ -24,6 +22,8 @@
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_source.h"
 #include "content/public/browser/web_contents.h"
+#include "googleurl/src/gurl.h"
+#include "third_party/skia/include/core/SkBitmap.h"
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
 #include "base/environment.h"
@@ -46,8 +46,7 @@ namespace {
 // updated. If there are such shortcuts, it schedules icon download and
 // update them when icons are downloaded. It observes TAB_CLOSING notification
 // and cancels all the work when the underlying tab is closing.
-class UpdateShortcutWorker : public content::NotificationObserver,
-                             public FaviconDownloadHelperDelegate {
+class UpdateShortcutWorker : public content::NotificationObserver {
  public:
   explicit UpdateShortcutWorker(WebContents* web_contents);
 
@@ -62,13 +61,13 @@ class UpdateShortcutWorker : public content::NotificationObserver,
   // Downloads icon via the FaviconTabHelper.
   void DownloadIcon();
 
-  // FaviconDownloadHelperDelegate override.
-  virtual void OnDidDownloadFavicon(
+  // Favicon download callback.
+  void DidDownloadFavicon(
       int id,
       const GURL& image_url,
       bool errored,
       int requested_size,
-      const std::vector<SkBitmap>& bitmaps) OVERRIDE;
+      const std::vector<SkBitmap>& bitmaps);
 
   // Checks if shortcuts exists on desktop, start menu and quick launch.
   void CheckExistingShortcuts();
@@ -157,26 +156,21 @@ void UpdateShortcutWorker::DownloadIcon() {
     return;
   }
 
-  scoped_ptr<FaviconDownloadHelper> download_helper(
-      new FaviconDownloadHelper(web_contents_, this));
-
-  download_helper->DownloadFavicon(unprocessed_icons_.back().url,
-                                   std::max(unprocessed_icons_.back().width,
-                                            unprocessed_icons_.back().height));
+  web_contents_->DownloadFavicon(
+      unprocessed_icons_.back().url,
+      std::max(unprocessed_icons_.back().width,
+               unprocessed_icons_.back().height),
+      base::Bind(&UpdateShortcutWorker::DidDownloadFavicon,
+                 base::Unretained(this)));
   unprocessed_icons_.pop_back();
 }
 
-void UpdateShortcutWorker::OnDidDownloadFavicon(
+void UpdateShortcutWorker::DidDownloadFavicon(
     int id,
     const GURL& image_url,
     bool errored,
     int requested_size,
     const std::vector<SkBitmap>& bitmaps) {
-  if (web_contents_ == NULL) {
-    DeleteMe();  // We are done if underlying WebContents is gone.
-    return;
-  }
-
   std::vector<ui::ScaleFactor> scale_factors;
   scale_factors.push_back(ui::SCALE_FACTOR_100P);
 
diff --git a/chrome/browser/ui/webui/ntp/app_launcher_handler.cc b/chrome/browser/ui/webui/ntp/app_launcher_handler.cc
index 58575f9..d899c96 100644
--- a/chrome/browser/ui/webui/ntp/app_launcher_handler.cc
+++ b/chrome/browser/ui/webui/ntp/app_launcher_handler.cc
@@ -39,12 +39,12 @@
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/extensions/extension_icon_set.h"
 #include "chrome/common/extensions/extension_resource.h"
-#include "chrome/common/favicon_url.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/common/web_apps.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/web_ui.h"
+#include "content/public/common/favicon_url.h"
 #include "googleurl/src/gurl.h"
 #include "grit/browser_resources.h"
 #include "grit/generated_resources.h"
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 793e473..8241bc2 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -585,9 +585,6 @@
         'browser/external_protocol/external_protocol_observer.cc',
         'browser/external_protocol/external_protocol_observer.h',
         'browser/external_tab/external_tab_container.h',
-        'browser/favicon/favicon_download_helper.cc',
-        'browser/favicon/favicon_download_helper.h',
-        'browser/favicon/favicon_download_helper_delegate.h',
         'browser/favicon/favicon_handler.cc',
         'browser/favicon/favicon_handler.h',
         'browser/favicon/favicon_handler_delegate.h',
diff --git a/chrome/chrome_common.gypi b/chrome/chrome_common.gypi
index 09f5044..1bbf113 100644
--- a/chrome/chrome_common.gypi
+++ b/chrome/chrome_common.gypi
@@ -217,8 +217,6 @@
         'common/extensions/api/extension_api_stub.cc',
         'common/external_ipc_fuzzer.h',
         'common/external_ipc_fuzzer.cc',
-        'common/favicon_url.cc',
-        'common/favicon_url.h',
         'common/form_data.cc',
         'common/form_data.h',
         'common/form_data_predictions.cc',
@@ -227,7 +225,6 @@
         'common/form_field_data.h',
         'common/form_field_data_predictions.cc',
         'common/form_field_data_predictions.h',
-        'common/icon_messages.h',
         'common/icon_with_badge_image_source.cc',
         'common/icon_with_badge_image_source.h',
         'common/instant_types.cc',
diff --git a/chrome/chrome_renderer.gypi b/chrome/chrome_renderer.gypi
index 102d02b..fb97800 100644
--- a/chrome/chrome_renderer.gypi
+++ b/chrome/chrome_renderer.gypi
@@ -129,8 +129,6 @@
         'renderer/extensions/web_request_custom_bindings.h',
         'renderer/extensions/webstore_bindings.cc',
         'renderer/extensions/webstore_bindings.h',
-        'renderer/favicon_helper.cc',
-        'renderer/favicon_helper.h',
         'renderer/frame_sniffer.cc',
         'renderer/frame_sniffer.h',
         'renderer/loadtimes_extension_bindings.h',
diff --git a/chrome/common/common_message_generator.h b/chrome/common/common_message_generator.h
index b6c06e9..9631798 100644
--- a/chrome/common/common_message_generator.h
+++ b/chrome/common/common_message_generator.h
@@ -8,7 +8,6 @@
 #include "chrome/common/benchmarking_messages.h"
 #include "chrome/common/chrome_utility_messages.h"
 #include "chrome/common/extensions/extension_messages.h"
-#include "chrome/common/icon_messages.h"
 #include "chrome/common/prerender_messages.h"
 #include "chrome/common/print_messages.h"
 #include "chrome/common/render_messages.h"
diff --git a/chrome/renderer/chrome_content_renderer_client.cc b/chrome/renderer/chrome_content_renderer_client.cc
index c7b30ab2..eb60f95 100644
--- a/chrome/renderer/chrome_content_renderer_client.cc
+++ b/chrome/renderer/chrome_content_renderer_client.cc
@@ -43,7 +43,6 @@
 #include "chrome/renderer/extensions/miscellaneous_bindings.h"
 #include "chrome/renderer/extensions/resource_request_policy.h"
 #include "chrome/renderer/external_extension.h"
-#include "chrome/renderer/favicon_helper.h"
 #include "chrome/renderer/loadtimes_extension_bindings.h"
 #include "chrome/renderer/net/renderer_net_predictor.h"
 #include "chrome/renderer/page_click_tracker.h"
@@ -305,8 +304,6 @@ void ChromeContentRendererClient::RenderViewCreated(
   new PepperHelper(render_view);
 #endif
 
-  // FaviconHelper will delete itself when render_view is destroyed.
-  new FaviconHelper(render_view);
   // Used only for testing/automation.
   if (CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kDomAutomationController)) {
diff --git a/chrome/renderer/chrome_render_view_observer.cc b/chrome/renderer/chrome_render_view_observer.cc
index b0503bb..8c764b5 100644
--- a/chrome/renderer/chrome_render_view_observer.cc
+++ b/chrome/renderer/chrome_render_view_observer.cc
@@ -13,7 +13,6 @@
 #include "base/string_util.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
-#include "chrome/common/favicon_url.h"
 #include "chrome/common/prerender_messages.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 7cc55b8..e4e4e6d 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -39,6 +39,7 @@
 #include "content/browser/web_contents/web_contents_view_guest.h"
 #include "content/browser/webui/web_ui_impl.h"
 #include "content/common/browser_plugin_messages.h"
+#include "content/common/icon_messages.h"
 #include "content/common/intents_messages.h"
 #include "content/common/ssl_status_serialization.h"
 #include "content/common/view_messages.h"
@@ -148,6 +149,17 @@ const int kSyncWaitDelay = 40;
 
 const char kDotGoogleDotCom[] = ".google.com";
 
+static int StartDownload(content::RenderViewHost* rvh,
+                         const GURL& url,
+                         int image_size) {
+  static int g_next_favicon_download_id = 0;
+  rvh->Send(new IconMsg_DownloadFavicon(rvh->GetRoutingID(),
+                                        ++g_next_favicon_download_id,
+                                        url,
+                                        image_size));
+  return g_next_favicon_download_id;
+}
+
 #if defined(OS_WIN)
 
 BOOL CALLBACK InvalidateWindow(HWND hwnd, LPARAM lparam) {
@@ -746,6 +758,8 @@ bool WebContentsImpl::OnMessageReceived(RenderViewHost* render_view_host,
                         OnRequestPpapiBrokerPermission)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_CreateGuest,
                         OnBrowserPluginCreateGuest)
+    IPC_MESSAGE_HANDLER(IconHostMsg_DidDownloadFavicon, OnDidDownloadFavicon)
+    IPC_MESSAGE_HANDLER(IconHostMsg_UpdateFaviconURL, OnUpdateFaviconURL)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP_EX()
   message_source_ = NULL;
@@ -1950,6 +1964,14 @@ void WebContentsImpl::DidEndColorChooser(int color_chooser_id) {
   color_chooser_ = NULL;
 }
 
+int WebContentsImpl::DownloadFavicon(const GURL& url, int image_size,
+                                     const FaviconDownloadCallback& callback) {
+  RenderViewHost* host = GetRenderViewHost();
+  int id = StartDownload(host, url, image_size);
+  favicon_download_map_[id] = callback;
+  return id;
+}
+
 bool WebContentsImpl::FocusLocationBarByDefault() {
   WebUI* web_ui = GetWebUIForCurrentState();
   if (web_ui)
@@ -2365,6 +2387,31 @@ void WebContentsImpl::OnBrowserPluginCreateGuest(
                                         params);
 }
 
+void WebContentsImpl::OnDidDownloadFavicon(
+    int id,
+    const GURL& image_url,
+    bool errored,
+    int requested_size,
+    const std::vector<SkBitmap>& bitmaps) {
+  FaviconDownloadMap::iterator iter = favicon_download_map_.find(id);
+  if (iter == favicon_download_map_.end()) {
+    // Currently WebContents notifies us of ANY downloads so that it is
+    // possible to get here.
+    return;
+  }
+  if (!iter->second.is_null()) {
+    iter->second.Run(id, image_url, errored, requested_size, bitmaps);
+  }
+  favicon_download_map_.erase(id);
+}
+
+void WebContentsImpl::OnUpdateFaviconURL(
+    int32 page_id,
+    const std::vector<FaviconURL>& candidates) {
+  FOR_EACH_OBSERVER(WebContentsObserver, observers_,
+                    DidUpdateFaviconURL(page_id, candidates));
+}
+
 void WebContentsImpl::DidBlock3DAPIs(const GURL& url,
                                      ThreeDAPIType requester) {
   FOR_EACH_OBSERVER(WebContentsObserver, observers_,
diff --git a/content/browser/web_contents/web_contents_impl.h b/content/browser/web_contents/web_contents_impl.h
index 2478406..cb4fdae 100644
--- a/content/browser/web_contents/web_contents_impl.h
+++ b/content/browser/web_contents/web_contents_impl.h
@@ -62,6 +62,7 @@ class WebContentsImpl;
 class WebContentsObserver;
 class WebContentsView;
 class WebContentsViewDelegate;
+struct FaviconURL;
 struct LoadNotificationDetails;
 
 // Factory function for the implementations that content knows about. Takes
@@ -277,6 +278,8 @@ class CONTENT_EXPORT WebContentsImpl
   virtual void DidChooseColorInColorChooser(int color_chooser_id,
                                             SkColor color) OVERRIDE;
   virtual void DidEndColorChooser(int color_chooser_id) OVERRIDE;
+  virtual int DownloadFavicon(const GURL& url, int image_size,
+                              const FaviconDownloadCallback& callback) OVERRIDE;
 
   // Implementation of PageNavigator.
   virtual WebContents* OpenURL(const OpenURLParams& params) OVERRIDE;
@@ -571,6 +574,13 @@ class CONTENT_EXPORT WebContentsImpl
   void OnBrowserPluginCreateGuest(
       int instance_id,
       const BrowserPluginHostMsg_CreateGuest_Params& params);
+  void OnDidDownloadFavicon(int id,
+                            const GURL& image_url,
+                            bool errored,
+                            int requested_size,
+                            const std::vector<SkBitmap>& bitmaps);
+  void OnUpdateFaviconURL(int32 page_id,
+                          const std::vector<FaviconURL>& candidates);
 
   // Changes the IsLoading state and notifies delegate as needed
   // |details| is used to provide details on the load that just finished
@@ -858,6 +868,10 @@ class CONTENT_EXPORT WebContentsImpl
   // outlive it.
   std::set<RenderWidgetHostImpl*> created_widgets_;
 
+  // Maps the ids of pending favicon downloads to their callbacks
+  typedef std::map<int, FaviconDownloadCallback> FaviconDownloadMap;
+  FaviconDownloadMap favicon_download_map_;
+
   DISALLOW_COPY_AND_ASSIGN(WebContentsImpl);
 };
 
diff --git a/content/common/content_message_generator.h b/content/common/content_message_generator.h
index 805a787..a11172e 100644
--- a/content/common/content_message_generator.h
+++ b/content/common/content_message_generator.h
@@ -26,6 +26,7 @@
 #include "content/common/geolocation_messages.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/common/hyphenator_messages.h"
+#include "content/common/icon_messages.h"
 #include "content/common/indexed_db/indexed_db_messages.h"
 #include "content/common/intents_messages.h"
 #include "content/common/java_bridge_messages.h"
diff --git a/chrome/common/icon_messages.h b/content/common/icon_messages.h
index 26e8f14..2cf1c15 100644
--- a/chrome/common/icon_messages.h
+++ b/content/common/icon_messages.h
@@ -5,7 +5,7 @@
 // Multiply-included message file, no traditional include guard.
 #include <vector>
 
-#include "chrome/common/favicon_url.h"
+#include "content/public/common/favicon_url.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_message_macros.h"
 #include "ipc/ipc_param_traits.h"
@@ -13,9 +13,9 @@
 
 #define IPC_MESSAGE_START IconMsgStart
 
-IPC_ENUM_TRAITS(FaviconURL::IconType)
+IPC_ENUM_TRAITS(content::FaviconURL::IconType)
 
-IPC_STRUCT_TRAITS_BEGIN(FaviconURL)
+IPC_STRUCT_TRAITS_BEGIN(content::FaviconURL)
   IPC_STRUCT_TRAITS_MEMBER(icon_url)
   IPC_STRUCT_TRAITS_MEMBER(icon_type)
 IPC_STRUCT_TRAITS_END()
@@ -35,7 +35,7 @@ IPC_MESSAGE_ROUTED3(IconMsg_DownloadFavicon,
 // Notification that the urls for the favicon of a site has been determined.
 IPC_MESSAGE_ROUTED2(IconHostMsg_UpdateFaviconURL,
                     int32 /* page_id */,
-                    std::vector<FaviconURL> /* urls of the favicon */)
+                    std::vector<content::FaviconURL> /* urls of the favicon */)
 
 IPC_MESSAGE_ROUTED5(IconHostMsg_DidDownloadFavicon,
                     int /* Identifier of the request */,
diff --git a/content/content_common.gypi b/content/content_common.gypi
index 8c5c4ca..3a7f550 100644
--- a/content/content_common.gypi
+++ b/content/content_common.gypi
@@ -39,6 +39,8 @@
     'public/common/console_message_level.h',
     'public/common/dx_diag_node.cc',
     'public/common/dx_diag_node.h',
+    'public/common/favicon_url.cc',
+    'public/common/favicon_url.h',
     'public/common/file_chooser_params.cc',
     'public/common/file_chooser_params.h',
     'public/common/frame_navigate_params.cc',
@@ -253,6 +255,7 @@
     'common/gpu/texture_image_transport_surface.cc',
     'common/handle_enumerator_win.cc',
     'common/handle_enumerator_win.h',
+    'common/icon_messages.h',
     'common/indexed_db/indexed_db_key.cc',
     'common/indexed_db/indexed_db_key.h',
     'common/indexed_db/indexed_db_key_path.cc',
diff --git a/content/content_renderer.gypi b/content/content_renderer.gypi
index 3058717..f296b70 100644
--- a/content/content_renderer.gypi
+++ b/content/content_renderer.gypi
@@ -81,6 +81,8 @@
     'renderer/dom_storage/webstoragenamespace_impl.h',
     'renderer/external_popup_menu.cc',
     'renderer/external_popup_menu.h',
+    'renderer/favicon_helper.cc',
+    'renderer/favicon_helper.h',
     'renderer/gamepad_shared_memory_reader.cc',
     'renderer/gamepad_shared_memory_reader.h',
     'renderer/geolocation_dispatcher.cc',
@@ -139,7 +141,7 @@
     'renderer/media/renderer_webaudiodevice_impl.cc',
     'renderer/media/renderer_webaudiodevice_impl.h',
     'renderer/media/rtc_media_constraints.cc',
-    'renderer/media/rtc_media_constraints.h', 
+    'renderer/media/rtc_media_constraints.h',
     'renderer/media/rtc_video_decoder.cc',
     'renderer/media/rtc_video_decoder.h',
     'renderer/media/rtc_video_renderer.cc',
@@ -334,7 +336,7 @@
         '../third_party/libjingle/libjingle.gyp:libjingle_p2p',
         '../third_party/libjingle/libjingle.gyp:libjingle_peerconnection',
         '../third_party/webrtc/system_wrappers/source/system_wrappers.gyp:system_wrappers',
-        '../third_party/webrtc/modules/modules.gyp:audio_device',        
+        '../third_party/webrtc/modules/modules.gyp:audio_device',
         '../third_party/webrtc/video_engine/video_engine.gyp:video_engine_core',
         '../third_party/webrtc/voice_engine/voice_engine.gyp:voice_engine_core',
         '<(DEPTH)/crypto/crypto.gyp:crypto',
@@ -353,7 +355,7 @@
         'renderer/media/rtc_video_capturer.cc',
         'renderer/media/rtc_video_capturer.h',
         'renderer/media/webrtc_audio_capturer.cc',
-        'renderer/media/webrtc_audio_capturer.h',         
+        'renderer/media/webrtc_audio_capturer.h',
         'renderer/media/webrtc_audio_device_impl.cc',
         'renderer/media/webrtc_audio_device_impl.h',
         'renderer/media/webrtc_audio_renderer.cc',
diff --git a/content/public/browser/web_contents.h b/content/public/browser/web_contents.h
index cab59f0..ebb06df 100644
--- a/content/public/browser/web_contents.h
+++ b/content/public/browser/web_contents.h
@@ -393,6 +393,23 @@ class WebContents : public PageNavigator,
 
   // Does this have an opener associated with it?
   virtual bool HasOpener() const = 0;
+
+  typedef base::Callback<void(int, /* id */
+                              const GURL&, /* image_url */
+                              bool, /* errored */
+                              int,  /* requested_size */
+                              const std::vector<SkBitmap>& /* bitmaps*/)>
+      FaviconDownloadCallback;
+
+  // Sends a request to download the given favicon |url| and returns the unique
+  // id of the download request. When the download is finished, |callback| will
+  // be called with the bitmaps received from the renderer. Note that
+  // |image_size| is a hint for images with multiple sizes. The downloaded image
+  // is not resized to the given image_size. If 0 is passed, the first frame of
+  // the image is returned.
+  virtual int DownloadFavicon(const GURL& url, int image_size,
+                              const FaviconDownloadCallback& callback) = 0;
+
 };
 
 }  // namespace content
diff --git a/content/public/browser/web_contents_observer.h b/content/public/browser/web_contents_observer.h
index 87f5f7e..a037efb 100644
--- a/content/public/browser/web_contents_observer.h
+++ b/content/public/browser/web_contents_observer.h
@@ -19,6 +19,7 @@ namespace content {
 class RenderViewHost;
 class WebContents;
 class WebContentsImpl;
+struct FaviconURL;
 struct FrameNavigateParams;
 struct LoadCommittedDetails;
 struct Referrer;
@@ -142,6 +143,10 @@ class CONTENT_EXPORT WebContentsObserver : public IPC::Listener,
   virtual void DidBlock3DAPIs(const GURL& url,
                               ThreeDAPIType requester) {}
 
+  // Invoked when new FaviconURL candidates are received from the renderer.
+  virtual void DidUpdateFaviconURL(int32 page_id,
+                                   const std::vector<FaviconURL>& candidates) {}
+
   // IPC::Listener implementation.
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
diff --git a/chrome/common/favicon_url.cc b/content/public/common/favicon_url.cc
index 8b05d0e..44f12bc6 100644
--- a/chrome/common/favicon_url.cc
+++ b/content/public/common/favicon_url.cc
@@ -2,7 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/common/favicon_url.h"
+#include "content/public/common/favicon_url.h"
+
+namespace content {
 
 FaviconURL::FaviconURL()
   : icon_type(INVALID_ICON) {
@@ -15,3 +17,5 @@ FaviconURL::FaviconURL(const GURL& url, IconType type)
 
 FaviconURL::~FaviconURL() {
 }
+
+} // namespace content
diff --git a/chrome/common/favicon_url.h b/content/public/common/favicon_url.h
index 4da256b..b1d13cb 100644
--- a/chrome/common/favicon_url.h
+++ b/content/public/common/favicon_url.h
@@ -2,13 +2,16 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_COMMON_FAVICON_URL_
-#define CHROME_COMMON_FAVICON_URL_
+#ifndef CONTENT_PUBLIC_COMMON_FAVICON_URL_
+#define CONTENT_PUBLIC_COMMON_FAVICON_URL_
 
+#include "content/common/content_export.h"
 #include "googleurl/src/gurl.h"
 
+namespace content {
+
 // The favicon url from the render.
-struct FaviconURL {
+struct CONTENT_EXPORT FaviconURL {
   // The icon type in a page. The definition must be same as history::IconType.
   enum IconType {
     INVALID_ICON = 0x0,
@@ -28,4 +31,6 @@ struct FaviconURL {
   IconType icon_type;
 };
 
-#endif  // CHROME_COMMON_FAVICON_URL_
+} // namespace content
+
+#endif  // CONTENT_PUBLIC_COMMON_FAVICON_URL_
diff --git a/content/public/renderer/render_view_observer.h b/content/public/renderer/render_view_observer.h
index b3f63b9..b99dc1d 100644
--- a/content/public/renderer/render_view_observer.h
+++ b/content/public/renderer/render_view_observer.h
@@ -49,8 +49,6 @@ class CONTENT_EXPORT RenderViewObserver : public IPC::Listener,
   // These match the WebKit API notifications
   virtual void DidStartLoading() {}
   virtual void DidStopLoading() {}
-  virtual void DidChangeIcon(WebKit::WebFrame* frame,
-                             WebKit::WebIconURL::Type) {}
   virtual void DidFinishDocumentLoad(WebKit::WebFrame* frame) {}
   virtual void DidFailLoad(WebKit::WebFrame* frame,
                            const WebKit::WebURLError& error) {}
diff --git a/chrome/renderer/favicon_helper.cc b/content/renderer/favicon_helper.cc
index 8df4839..31d97a8 100644
--- a/chrome/renderer/favicon_helper.cc
+++ b/content/renderer/favicon_helper.cc
@@ -2,19 +2,19 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/renderer/favicon_helper.h"
+#include "content/renderer/favicon_helper.h"
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/message_loop.h"
-#include "chrome/common/chrome_constants.h"
-#include "chrome/common/favicon_url.h"
-#include "chrome/common/icon_messages.h"
+#include "content/common/icon_messages.h"
 #include "content/public/renderer/render_view.h"
 #include "net/base/data_url.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebURLRequest.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebVector.h"
+#include "ui/base/ui_base_switches.h"
 #include "ui/gfx/favicon_size.h"
 #include "ui/gfx/size.h"
 #include "ui/gfx/skbitmap_operations.h"
@@ -29,6 +29,21 @@ using WebKit::WebURL;
 using WebKit::WebURLRequest;
 using webkit_glue::MultiResolutionImageResourceFetcher;
 
+namespace content {
+
+namespace {
+bool TouchEnabled() {
+// Based on the definition of chrome::kEnableTouchIcon.
+#if defined(OS_ANDROID)
+  return true;
+#else
+  return false;
+#endif
+}
+
+} // namespace
+
+
 static FaviconURL::IconType ToFaviconType(WebIconURL::Type type) {
   switch (type) {
     case WebIconURL::TypeFavicon:
@@ -43,8 +58,25 @@ static FaviconURL::IconType ToFaviconType(WebIconURL::Type type) {
   return FaviconURL::INVALID_ICON;
 }
 
-FaviconHelper::FaviconHelper(content::RenderView* render_view)
-    : content::RenderViewObserver(render_view) {
+FaviconHelper::FaviconHelper(RenderView* render_view)
+    : RenderViewObserver(render_view) {
+}
+
+void FaviconHelper::DidChangeIcon(WebKit::WebFrame* frame,
+                                  WebKit::WebIconURL::Type icon_type) {
+  if (frame->parent())
+    return;
+
+  if (!TouchEnabled() && icon_type != WebIconURL::TypeFavicon)
+    return;
+
+  WebVector<WebIconURL> icon_urls = frame->iconURLs(icon_type);
+  std::vector<FaviconURL> urls;
+  for (size_t i = 0; i < icon_urls.size(); i++) {
+    urls.push_back(FaviconURL(icon_urls[i].iconURL(),
+                              ToFaviconType(icon_urls[i].iconType())));
+  }
+  SendUpdateFaviconURL(routing_id(), render_view()->GetPageId(), urls);
 }
 
 FaviconHelper::~FaviconHelper() {
@@ -139,7 +171,7 @@ bool FaviconHelper::OnMessageReceived(const IPC::Message& message) {
 
 void FaviconHelper::DidStopLoading() {
   int icon_types = WebIconURL::TypeFavicon;
-  if (chrome::kEnableTouchIcon)
+  if (TouchEnabled())
     icon_types |= WebIconURL::TypeTouchPrecomposed | WebIconURL::TypeTouch;
 
   WebVector<WebIconURL> icon_urls =
@@ -153,20 +185,4 @@ void FaviconHelper::DidStopLoading() {
   SendUpdateFaviconURL(routing_id(), render_view()->GetPageId(), urls);
 }
 
-void FaviconHelper::DidChangeIcon(WebKit::WebFrame* frame,
-                                  WebKit::WebIconURL::Type icon_type) {
-  if (frame->parent())
-    return;
-
-  if (!chrome::kEnableTouchIcon &&
-      icon_type != WebIconURL::TypeFavicon)
-    return;
-
-  WebVector<WebIconURL> icon_urls = frame->iconURLs(icon_type);
-  std::vector<FaviconURL> urls;
-  for (size_t i = 0; i < icon_urls.size(); i++) {
-    urls.push_back(FaviconURL(icon_urls[i].iconURL(),
-                              ToFaviconType(icon_urls[i].iconType())));
-  }
-  SendUpdateFaviconURL(routing_id(), render_view()->GetPageId(), urls);
-}
+} // namespace content
diff --git a/chrome/renderer/favicon_helper.h b/content/renderer/favicon_helper.h
index aeccd28..acce508 100644
--- a/chrome/renderer/favicon_helper.h
+++ b/content/renderer/favicon_helper.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_RENDERER_FAVICON_HELPER_H_
-#define CHROME_RENDERER_FAVICON_HELPER_H_
+#ifndef CONTENT_RENDERER_FAVICON_HELPER_H_
+#define CONTENT_RENDERER_FAVICON_HELPER_H_
 
 #include <string>
 #include <vector>
@@ -13,18 +13,29 @@
 #include "content/public/renderer/render_view_observer.h"
 #include "googleurl/src/gurl.h"
 
-struct FaviconURL;
 class SkBitmap;
 
+namespace content {
+struct FaviconURL;
+}
+
 namespace webkit_glue {
 class MultiResolutionImageResourceFetcher;
 }
 
+namespace content {
+
+struct FaviconURL;
+
 // This class deals with favicon downloading.
 // There is one FaviconHelper per RenderView, which is owned by the RenderView.
-class FaviconHelper : public content::RenderViewObserver {
+class FaviconHelper : public RenderViewObserver {
  public:
-  explicit FaviconHelper(content::RenderView* render_view);
+  explicit FaviconHelper(RenderView* render_view);
+
+  // Sund a message that the favicon has changed.
+  void DidChangeIcon(WebKit::WebFrame* frame,
+                     WebKit::WebIconURL::Type icon_type);
 
  private:
   virtual ~FaviconHelper();
@@ -60,8 +71,6 @@ class FaviconHelper : public content::RenderViewObserver {
   // RenderViewObserver implementation.
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
   virtual void DidStopLoading() OVERRIDE;
-  virtual void DidChangeIcon(WebKit::WebFrame* frame,
-                             WebKit::WebIconURL::Type icon_type) OVERRIDE;
 
   typedef ScopedVector<webkit_glue::MultiResolutionImageResourceFetcher>
     ImageResourceFetcherList;
@@ -72,4 +81,6 @@ class FaviconHelper : public content::RenderViewObserver {
   DISALLOW_COPY_AND_ASSIGN(FaviconHelper);
 };
 
-#endif  // CHROME_RENDERER_FAVICON_HELPER_H_
+} // namespace content
+
+#endif  // CONTENT_RENDERER_FAVICON_HELPER_H_
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index c98827e..cd37848 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -73,6 +73,7 @@
 #include "content/renderer/dom_storage/webstoragenamespace_impl.h"
 #include "content/renderer/do_not_track_bindings.h"
 #include "content/renderer/external_popup_menu.h"
+#include "content/renderer/favicon_helper.h"
 #include "content/renderer/geolocation_dispatcher.h"
 #include "content/renderer/gpu/compositor_thread.h"
 #include "content/renderer/gpu/compositor_output_surface.h"
@@ -587,6 +588,7 @@ RenderViewImpl::RenderViewImpl(RenderViewImplParams* params)
       renderer_accessibility_(NULL),
       java_bridge_dispatcher_(NULL),
       mouse_lock_dispatcher_(NULL),
+      favicon_helper_(NULL),
 #if defined(OS_ANDROID)
       body_background_color_(SK_ColorWHITE),
       update_frame_info_scheduled_(false),
@@ -705,6 +707,7 @@ RenderViewImpl::RenderViewImpl(RenderViewImplParams* params)
   devtools_agent_ = new DevToolsAgent(this);
   mouse_lock_dispatcher_ = new RenderViewMouseLockDispatcher(this);
   intents_host_ = new WebIntentsHost(this);
+  favicon_helper_ = new FaviconHelper(this);
 
   // Create renderer_accessibility_ if needed.
   OnSetAccessibilityMode(params->accessibility_mode);
@@ -3513,8 +3516,7 @@ void RenderViewImpl::didReceiveTitle(WebFrame* frame, const WebString& title,
 }
 
 void RenderViewImpl::didChangeIcon(WebFrame* frame, WebIconURL::Type type) {
-  FOR_EACH_OBSERVER(RenderViewObserver, observers_,
-                    DidChangeIcon(frame, type));
+  favicon_helper_->DidChangeIcon(frame, type);
 }
 
 void RenderViewImpl::didFinishDocumentLoad(WebFrame* frame) {
diff --git a/content/renderer/render_view_impl.h b/content/renderer/render_view_impl.h
index 2fd89e7..bd61b92 100644
--- a/content/renderer/render_view_impl.h
+++ b/content/renderer/render_view_impl.h
@@ -143,6 +143,7 @@ class DevToolsAgent;
 class DocumentState;
 class DomAutomationController;
 class ExternalPopupMenu;
+class FaviconHelper;
 class GeolocationDispatcher;
 class InputTagSpeechDispatcher;
 class JavaBridgeDispatcher;
@@ -1404,6 +1405,9 @@ class CONTENT_EXPORT RenderViewImpl
   // Mouse Lock dispatcher attached to this view.
   MouseLockDispatcher* mouse_lock_dispatcher_;
 
+  // Helper class to handle favicon changes.
+  FaviconHelper* favicon_helper_;
+
 #if defined(OS_ANDROID)
   // Android Specific ---------------------------------------------------------