Added support for critical notification on low battery.

chrome/browser/chromeos/notifications/system_notification.cc

 // Copyright (c) 2010 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/chromeos/notifications/system_notification.h"
 
+#include "app/resource_bundle.h"
+#include "base/base64.h"
 #include "base/move.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/notifications/system_notification_factory.h"
 #include "chrome/browser/notifications/notification.h"
 #include "chrome/browser/notifications/notification_ui_manager.h"
 
 namespace chromeos {
 
 SystemNotification::SystemNotification(Profile* profile, std::string id,
-                                       string16 title)
+                                       int icon_resource_id, string16 title)
   : profile_(profile),
     collection_(static_cast<BalloonCollectionImpl*>(
       g_browser_process->notification_ui_manager()->balloon_collection())),
     delegate_(new Delegate(base::move(id))),
     title_(move(title)),
-    visible_(false) {}
+    visible_(false),
+    urgent_(false) {
+  // Load resource icon and covert to base64 encoded data url
+  scoped_refptr<RefCountedMemory> raw_icon(ResourceBundle::GetSharedInstance().
+      LoadDataResourceBytes(icon_resource_id));
+  std::string str_gurl;
+  std::copy(raw_icon->front(), raw_icon->front() + raw_icon->size(),
+            std::back_inserter(str_gurl));
+  base::Base64Encode(str_gurl, &str_gurl);
+  str_gurl.insert(0, "data:image/png;base64,");
+  GURL tmp_gurl(str_gurl);
+  icon_.Swap(&tmp_gurl);
+}
 
 SystemNotification::~SystemNotification() {
   Hide();
 }
 
-void SystemNotification::Show(const string16& message) {
-  Notification notify = SystemNotificationFactory::Create(GURL(),
+void SystemNotification::Show(const string16& message, bool urgent) {
+  Notification notify = SystemNotificationFactory::Create(icon_,
       title_, message, delegate_.get());
   if (visible_) {
-    collection_->UpdateNotification(notify);
+    // Force showing a user hidden notification on an urgent transition.
+    if (urgent && !urgent_) {
+      collection_->UpdateAndShowNotification(notify);
+    } else {
+      collection_->UpdateNotification(notify);
+    }
   } else {
     collection_->AddSystemNotification(notify, profile_, true /* sticky */,
                                        false /* no controls */);
-    visible_ = true;
   }
+  visible_ = true;
+  urgent_ = urgent;
 }
 
 void SystemNotification::Hide() {
   if (visible_) {
     collection_->Remove(Notification(GURL(), GURL(), std::wstring(),
                                      delegate_.get()));
 
     visible_ = false;
+    urgent_ = false;
   }
 }
 
 }  // namespace chromeos