Load user custom wallpaper after browser crash.

ash/shell.cc

Index: ash/shell.cc
diff --git a/ash/shell.cc b/ash/shell.cc
index 4731c74c939b8421cdb0f63305c6dfb268695dc5..1b182c6e68fe383df7b762f0f5d5c7595f45a51c 100644
--- a/ash/shell.cc
+++ b/ash/shell.cc
@@ -232,8 +232,7 @@ class DummyUserWallpaperDelegate : public UserWallpaperDelegate {
 
   virtual ~DummyUserWallpaperDelegate() {}
 
-  virtual const int GetUserWallpaperIndex() OVERRIDE {
-    return -1;
+  virtual void SetLoggedInUserWallpaper() OVERRIDE {
   }
 
   virtual void OpenSetWallpaperPage() OVERRIDE {
@@ -742,7 +741,7 @@ void Shell::Init() {
 
   // It needs to be created after OnWindowResized has been called, otherwise the
   // widget will not paint when restoring after a browser crash.
-  desktop_background_controller_->SetLoggedInUserWallpaper();
+  user_wallpaper_delegate_->SetLoggedInUserWallpaper();
 
   window_modality_controller_.reset(new internal::WindowModalityController);
   AddRootWindowEventFilter(window_modality_controller_.get());