Remove balloon notification code. The last user was the Linux GTK port but that's deleted now.

chrome/browser/notifications/notification.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/notifications/notification.h"
 
 #include "base/strings/string_util.h"
 #include "chrome/browser/notifications/desktop_notification_service.h"
 #include "ui/base/webui/web_ui_util.h"
 #include "ui/message_center/message_center_util.h"
@@ skipping 65 matching lines @@
                                    display_source,
                                    notifier_id,
                                    rich_notification_data,
                                    delegate),
       origin_url_(origin_url),
       is_html_(false),
       replace_id_(replace_id),
       delegate_(delegate) {
   // It's important to leave |icon_url_| empty with rich notifications enabled,
   // to prevent "Downloading" the data url and overwriting the existing |icon|.
-  if (!message_center::IsRichNotificationEnabled()) {
-    // "Upconvert" the string parameters to a data: URL.  Some balloon views
-    // require content URL to render anything, so this serves as a backup.
-    if (!icon.IsEmpty())
-      icon_url_ = GURL(webui::GetBitmapDataUrl(*icon.ToSkBitmap()));
-    content_url_ = GURL(
-        DesktopNotificationService::CreateDataUrl(icon_url_, title, body, dir));
-  }
 }
 
 Notification::Notification(const GURL& origin_url,
                            const gfx::Image& icon,
                            const base::string16& title,
                            const base::string16& body,
                            blink::WebTextDirection dir,
                            const base::string16& display_source,
                            const base::string16& replace_id,
                            NotificationDelegate* delegate)
@@ skipping 31 matching lines @@
   icon_url_ = notification.icon_url();
   is_html_ = notification.is_html();
   content_url_ = notification.content_url();
   button_one_icon_url_ = notification.button_one_icon_url();
   button_two_icon_url_ = notification.button_two_icon_url();
   image_url_ = notification.image_url();
   replace_id_ = notification.replace_id();
   delegate_ = notification.delegate();
   return *this;
 }