Delay wallpaper load by 2 * average wallpaper load time.

chrome/browser/chromeos/login/wallpaper_manager.cc

 // Copyright (c) 2013 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/login/wallpaper_manager.h"
 
 #include <vector>
 
 #include "ash/shell.h"
 #include "base/command_line.h"
@@ skipping 281 matching lines @@
             BrowserThread::UI, FROM_HERE,
             base::Bind(&WallpaperManager::CacheUsersWallpapers,
                        weak_factory_.GetWeakPtr()),
             base::TimeDelta::FromMilliseconds(kCacheWallpaperDelayMs));
       } else {
         should_cache_wallpaper_ = true;
       }
       break;
     }
     case chrome::NOTIFICATION_WALLPAPER_ANIMATION_FINISHED: {
+      NotifyAnimationFinished();
       if (should_cache_wallpaper_) {
         BrowserThread::PostDelayedTask(
             BrowserThread::UI, FROM_HERE,
             base::Bind(&WallpaperManager::CacheUsersWallpapers,
                        weak_factory_.GetWeakPtr()),
             base::TimeDelta::FromMilliseconds(kCacheWallpaperDelayMs));
         should_cache_wallpaper_ = false;
       }
       break;
     }
@@ skipping 272 matching lines @@
   // login. If UpdateWallpaper is called at GAIA login screen, no wallpaper will
   // be set. It could result a black screen on external monitors.
   // See http://crbug.com/265689 for detail.
   if (last_selected_user_.empty()) {
     SetDefaultWallpaper();
     return;
   }
   SetUserWallpaper(last_selected_user_);
 }
 
+void WallpaperManager::AddObserver(
+    base::WeakPtr<WallpaperManager::Observer> observer) {
+  ObserverList::iterator i = observers_.begin();
+  while (i != observers_.end()) {
+    if (*i != NULL) {
+      if (i->get() == observer.get())
+        return;
+      ++i;
+      continue;
+    }
+    observers_.erase(i++);
+  }
+  observers_.push_back(observer);
+}
+
+void WallpaperManager::NotifyAnimationFinished() {
+  ObserverList::iterator i = observers_.begin();
+  while (i != observers_.end()) {
+    if (*i != NULL) {
+      (*i)->OnWallpaperAnimationFinished(last_selected_user_);
+      ++i;
+      continue;
+    }
+    observers_.erase(i++);
+  }
+}
+
 // WallpaperManager, private: --------------------------------------------------
 
 void WallpaperManager::CacheUsersWallpapers() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   UserList users = UserManager::Get()->GetUsers();
 
   if (!users.empty()) {
     UserList::const_iterator it = users.begin();
     // Skip the wallpaper of first user in the list. It should have been cached.
     it++;
@@ skipping 363 matching lines @@
   // |sequence_token_| here.
   wallpaper_loader_->Start(wallpaper_path.value(), 0, sequence_token_,
                            base::Bind(&WallpaperManager::OnWallpaperDecoded,
                                       base::Unretained(this),
                                       email,
                                       info.layout,
                                       update_wallpaper));
 }
 
 }  // namespace chromeos