Load 2x resources on demand

chrome/browser/chromeos/login/wallpaper_manager.cc

Index: chrome/browser/chromeos/login/wallpaper_manager.cc
diff --git a/chrome/browser/chromeos/login/wallpaper_manager.cc b/chrome/browser/chromeos/login/wallpaper_manager.cc
index 2b03b28172f48a0ecc062993ab8f91174efb5cb7..8229d6311d4c04f54b8445be5e4a4f56255c5fc5 100644
--- a/chrome/browser/chromeos/login/wallpaper_manager.cc
+++ b/chrome/browser/chromeos/login/wallpaper_manager.cc
@@ -72,14 +72,8 @@ gfx::ImageSkia GetWallpaperThumbnail(const gfx::ImageSkia& wallpaper) {
       skia::ImageOperations::RESIZE_LANCZOS3,
       gfx::Size(kThumbnailWidth, kThumbnailHeight));
 
-  // Ideally, this would call thumbnail.GetRepresentations(). But since that
-  // isn't exposed on non-mac yet, we have to do this here.
-  std::vector<ui::ScaleFactor> scales = ui::GetSupportedScaleFactors();
-  for (size_t i = 0; i < scales.size(); ++i) {
-    if (wallpaper.HasRepresentation(scales[i]))
-      thumbnail.GetRepresentation(scales[i]);
-  }
-
+  thumbnail.EnsureRepsForSupportedScaleFactors();
+  thumbnail.SetReadOnly();
   return thumbnail;
 }
 
@@ -90,6 +84,7 @@ gfx::ImageSkia ImageSkiaDeepCopy(const gfx::ImageSkia& image) {
       iter != reps.end(); ++iter) {
     copy.AddRepresentation(*iter);
   }
+  copy.SetReadOnly();
   return copy;
 }
 
@@ -191,7 +186,7 @@ gfx::ImageSkia WallpaperManager::GetCustomWallpaperThumbnail(
     const std::string& email) {
   CustomWallpaperMap::const_iterator it =
       custom_wallpaper_thumbnail_cache_.find(email);
-  if (it != custom_wallpaper_cache_.end())
+  if (it != custom_wallpaper_thumbnail_cache_.end())
     return (*it).second;
   else
     return gfx::ImageSkia();
@@ -529,13 +524,12 @@ void WallpaperManager::CacheWallpaper(const std::string& email,
                                       const UserImage& wallpaper) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(custom_wallpaper_cache_.find(email) == custom_wallpaper_cache_.end());
-
   BrowserThread::PostTask(
       BrowserThread::FILE,
       FROM_HERE,
       base::Bind(&WallpaperManager::CacheThumbnail,
                  base::Unretained(this), email,
-                 ImageSkiaDeepCopy(wallpaper.image())));
+                 wallpaper.image().DeepCopy()));
 
   custom_wallpaper_cache_.insert(std::make_pair(email, wallpaper.image()));
 }
@@ -550,13 +544,12 @@ void WallpaperManager::FetchWallpaper(const std::string& email,
                                       ash::WallpaperLayout layout,
                                       const UserImage& wallpaper) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
   BrowserThread::PostTask(
       BrowserThread::FILE,
       FROM_HERE,
       base::Bind(&WallpaperManager::CacheThumbnail,
                  base::Unretained(this), email,
-                 ImageSkiaDeepCopy(wallpaper.image())));
+                 wallpaper.image().DeepCopy()));
 
   custom_wallpaper_cache_.insert(std::make_pair(email, wallpaper.image()));
   ash::Shell::GetInstance()->desktop_background_controller()->