Remove use of index in wallpaper picker code and some refactor

ash/desktop_background/desktop_background_view.cc

 // Copyright (c) 2012 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 "ash/desktop_background/desktop_background_view.h"
 
 #include <limits>
 
 #include "ash/ash_export.h"
 #include "ash/desktop_background/desktop_background_controller.h"
@@ skipping 110 matching lines @@
   // necessary to fill the background. Ideally the image should be larger
   // than the largest display supported, if not we will center it rather than
   // streching to avoid upsampling artifacts (Note that we could tile too, but
   // decided not to do this at the moment).
   DesktopBackgroundController* controller =
       ash::Shell::GetInstance()->desktop_background_controller();
   gfx::ImageSkia wallpaper = controller->GetWallpaper();
   WallpaperLayout wallpaper_layout = controller->GetWallpaperLayout();
 
   gfx::Rect wallpaper_rect(0, 0, wallpaper.width(), wallpaper.height());
-  if (wallpaper_layout == ash::CENTER_CROPPED && wallpaper.width() > width()
-      && wallpaper.height() > height()) {
+  if (wallpaper_layout == WALLPAPER_LAYOUT_CENTER_CROPPED &&
+      wallpaper.width() > width() && wallpaper.height() > height()) {
     // The dimension with the smallest ratio must be cropped, the other one
     // is preserved. Both are set in gfx::Size cropped_size.
     double horizontal_ratio = static_cast<double>(width()) /
         static_cast<double>(wallpaper.width());
     double vertical_ratio = static_cast<double>(height()) /
         static_cast<double>(wallpaper.height());
 
     gfx::Size cropped_size;
     if (vertical_ratio > horizontal_ratio) {
       cropped_size = gfx::Size(
           RoundPositive(static_cast<double>(width()) / vertical_ratio),
           wallpaper.height());
     } else {
       cropped_size = gfx::Size(wallpaper.width(),
           RoundPositive(static_cast<double>(height()) / horizontal_ratio));
     }
 
     gfx::Rect wallpaper_cropped_rect = wallpaper_rect;
     wallpaper_cropped_rect.ClampToCenteredSize(cropped_size);
     canvas->DrawImageInt(wallpaper,
         wallpaper_cropped_rect.x(), wallpaper_cropped_rect.y(),
         wallpaper_cropped_rect.width(), wallpaper_cropped_rect.height(),
         0, 0, width(), height(),
         true);
-  } else if (wallpaper_layout == ash::TILE) {
+  } else if (wallpaper_layout == WALLPAPER_LAYOUT_TILE) {
     canvas->TileImageInt(wallpaper, 0, 0, width(), height());
-  } else if (wallpaper_layout == ash::STRETCH) {
+  } else if (wallpaper_layout == WALLPAPER_LAYOUT_STRETCH) {
     // This is generally not recommended as it may show artifacts.
     canvas->DrawImageInt(wallpaper, 0, 0, wallpaper.width(),
         wallpaper.height(), 0, 0, width(), height(), true);
   } else {
     // All other are simply centered, and not scaled (but may be clipped).
      canvas->DrawImageInt(wallpaper, (width() - wallpaper.width()) / 2,
          (height() - wallpaper.height()) / 2);
   }
 }
 
@@ skipping 43 matching lines @@
   settings.AddObserver(new ShowWallpaperAnimationObserver(
       root_window, desktop_widget,
       wallpaper_delegate->ShouldShowInitialAnimation()));
   desktop_widget->Show();
   desktop_widget->GetNativeView()->SetName("DesktopBackgroundView");
   return desktop_widget;
 }
 
 }  // namespace internal
 }  // namespace ash