chromeos: Refactor shelf to create ShelfView earlier in startup

ash/root_window_controller.h

Index: ash/root_window_controller.h
diff --git a/ash/root_window_controller.h b/ash/root_window_controller.h
index 6f0945fd821330bad199472a4581507d4bd73ec5..493e9d94f63c0a8afe86fb67086532a0c6cc63c2 100644
--- a/ash/root_window_controller.h
+++ b/ash/root_window_controller.h
@@ -138,13 +138,11 @@ class ASH_EXPORT RootWindowController : public ShellObserver {
   wm::WorkspaceWindowState GetWorkspaceWindowState();
 
   WmShelf* wm_shelf() const { return wm_shelf_.get(); }
+  // TODO(jamescook): Eliminate in favor of wm_shelf().
+  WmShelf* GetShelf() const { return wm_shelf_.get(); }
 
-  bool HasShelf();
-
-  WmShelf* GetShelf();
-
-  // Creates the shelf view for this root window and notifies observers.
-  void CreateShelfView();
+  // Initializes the shelf for this root window and notifies observers.
+  void InitializeShelf();
 
   // Get touch HUDs associated with this root window controller.
   TouchHudDebug* touch_hud_debug() const { return touch_hud_debug_; }
@@ -352,6 +350,10 @@ class ASH_EXPORT RootWindowController : public ShellObserver {
   // to it during construction of the shelf widget and status tray.
   std::unique_ptr<WmShelf> wm_shelf_;
 
+  // TODO(jamescook): Eliminate this. It is left over from legacy shelf code and
+  // doesn't mean anything in particular.
+  bool shelf_initialized_ = false;
+
   std::unique_ptr<SystemWallpaperController> system_wallpaper_;
 
   std::unique_ptr<BootSplashScreen> boot_splash_screen_;