Remove use of index in wallpaper picker code and some refactor

ash/desktop_background/desktop_background_controller.cc

Index: ash/desktop_background/desktop_background_controller.cc
diff --git a/ash/desktop_background/desktop_background_controller.cc b/ash/desktop_background/desktop_background_controller.cc
index 8575c1e0176941e4d0df8e02ec8923f397ce1539..9639196b2bcac06f5c3181c3bede5658078a6e07 100644
--- a/ash/desktop_background/desktop_background_controller.cc
+++ b/ash/desktop_background/desktop_background_controller.cc
@@ -18,6 +18,7 @@
 #include "base/synchronization/cancellation_flag.h"
 #include "base/threading/worker_pool.h"
 #include "content/public/browser/browser_thread.h"
+#include "grit/ash_wallpaper_resources.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
 #include "ui/base/resource/resource_bundle.h"
@@ -43,6 +44,24 @@ internal::RootWindowLayoutManager* GetRootWindowLayoutManager(
 }
 }  // namespace
 
+#if defined(GOOGLE_CHROME_BUILD)
+const WallpaperInfo kDefaultLargeWallpaper =
+    { IDR_AURA_WALLPAPERS_2_LANDSCAPE8_LARGE, WALLPAPER_LAYOUT_CENTER_CROPPED };
+const WallpaperInfo kDefaultSmallWallpaper =
+    { IDR_AURA_WALLPAPERS_2_LANDSCAPE8_SMALL, WALLPAPER_LAYOUT_CENTER };
+const WallpaperInfo kGuestLargeWallpaper =
+    { IDR_AURA_WALLPAPERS_2_LANDSCAPE7_LARGE, WALLPAPER_LAYOUT_CENTER_CROPPED };
+const WallpaperInfo kGuestSmallWallpaper =
+    { IDR_AURA_WALLPAPERS_2_LANDSCAPE7_SMALL, WALLPAPER_LAYOUT_CENTER };
+#else
+const WallpaperInfo kDefaultLargeWallpaper =
+    { IDR_AURA_WALLPAPERS_5_GRADIENT5_LARGE, WALLPAPER_LAYOUT_TILE };
+const WallpaperInfo kDefaultSmallWallpaper =
+    { IDR_AURA_WALLPAPERS_5_GRADIENT5_SMALL, WALLPAPER_LAYOUT_TILE };
+const WallpaperInfo kGuestLargeWallpaper = kDefaultLargeWallpaper;
+const WallpaperInfo kGuestSmallWallpaper = kDefaultSmallWallpaper;
+#endif
+
 const int kSmallWallpaperMaxWidth = 1366;
 const int kSmallWallpaperMaxHeight = 800;
 const int kLargeWallpaperMaxWidth = 2560;
@@ -50,52 +69,40 @@ const int kLargeWallpaperMaxHeight = 1700;
 
 // Stores the current wallpaper data.
 struct DesktopBackgroundController::WallpaperData {
-  WallpaperData(int index, WallpaperResolution resolution)
-      : is_default_wallpaper(true),
-        wallpaper_index(index),
-        wallpaper_layout(GetWallpaperViewInfo(index, resolution).layout),
+  explicit WallpaperData(const WallpaperInfo& info)
+      : wallpaper_info(info),
         wallpaper_image(*(ui::ResourceBundle::GetSharedInstance().GetImageNamed(
-            GetWallpaperViewInfo(index, resolution).id).ToImageSkia())) {
+            info.idr).ToImageSkia())) {
   }
-  WallpaperData(WallpaperLayout layout, const gfx::ImageSkia& image)
-      : is_default_wallpaper(false),
-        wallpaper_index(-1),
-        wallpaper_layout(layout),
+  WallpaperData(const WallpaperInfo& info, const gfx::ImageSkia& image)
+      : wallpaper_info(info),
         wallpaper_image(image) {
   }
-  const bool is_default_wallpaper;
-  const int wallpaper_index;
-  const WallpaperLayout wallpaper_layout;
+  const WallpaperInfo wallpaper_info;
   const gfx::ImageSkia wallpaper_image;
 };
 
-// DesktopBackgroundController::WallpaperOperation wraps background wallpaper
+// DesktopBackgroundController::WallpaperLoader wraps background wallpaper
 // loading.
-class DesktopBackgroundController::WallpaperOperation
+class DesktopBackgroundController::WallpaperLoader
     : public base::RefCountedThreadSafe<
-          DesktopBackgroundController::WallpaperOperation> {
+          DesktopBackgroundController::WallpaperLoader> {
  public:
-  WallpaperOperation(int index, WallpaperResolution resolution)
-      : index_(index),
-        resolution_(resolution) {
-  }
-
-  static void Run(scoped_refptr<WallpaperOperation> wo) {
-    wo->LoadingWallpaper();
+  explicit WallpaperLoader(const WallpaperInfo& info)
+      : info_(info) {
   }
 
-  void LoadingWallpaper() {
-    if (cancel_flag_.IsSet())
-      return;
-    wallpaper_data_.reset(new WallpaperData(index_, resolution_));
+  static void LoadOnWorkerPoolThread(scoped_refptr<WallpaperLoader> wl) {
+    DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
+    wl->LoadingWallpaper();
   }
 
   void Cancel() {
     cancel_flag_.Set();
   }
 
-  int index() const {
-    return index_;
+  int idr() const {
+    return info_.idr;
   }
 
   WallpaperData* ReleaseWallpaperData() {
@@ -104,19 +111,23 @@ class DesktopBackgroundController::WallpaperOperation
 
  private:
   friend class base::RefCountedThreadSafe<
-      DesktopBackgroundController::WallpaperOperation>;
+      DesktopBackgroundController::WallpaperLoader>;
 
-  ~WallpaperOperation() {}
+  void LoadingWallpaper() {
+    if (cancel_flag_.IsSet())
+      return;
+    wallpaper_data_.reset(new WallpaperData(info_));
+  }
+
+  ~WallpaperLoader() {}
 
   base::CancellationFlag cancel_flag_;
 
   scoped_ptr<WallpaperData> wallpaper_data_;
 
-  const int index_;
-
-  const WallpaperResolution resolution_;
+  const WallpaperInfo info_;
 
-  DISALLOW_COPY_AND_ASSIGN(WallpaperOperation);
+  DISALLOW_COPY_AND_ASSIGN(WallpaperLoader);
 };
 
 DesktopBackgroundController::DesktopBackgroundController()
@@ -148,8 +159,8 @@ void DesktopBackgroundController::RemoveObserver(
 
 WallpaperLayout DesktopBackgroundController::GetWallpaperLayout() const {
   if (current_wallpaper_.get())
-    return current_wallpaper_->wallpaper_layout;
-  return CENTER_CROPPED;
+    return current_wallpaper_->wallpaper_info.layout;
+  return WALLPAPER_LAYOUT_CENTER_CROPPED;
 }
 
 gfx::ImageSkia DesktopBackgroundController::GetCurrentWallpaperImage() {
@@ -158,6 +169,15 @@ gfx::ImageSkia DesktopBackgroundController::GetCurrentWallpaperImage() {
   return GetWallpaper();
 }
 
+int DesktopBackgroundController::GetWallpaperIDR() const {
+  if (wallpaper_loader_.get())
+    return wallpaper_loader_->idr();
+  else if (current_wallpaper_.get())
+    return current_wallpaper_->wallpaper_info.idr;
+  else
+    return -1;
+}
+
 void DesktopBackgroundController::OnRootWindowAdded(
     aura::RootWindow* root_window) {
   // Handle resolution change for "built-in" images."
@@ -168,69 +188,30 @@ void DesktopBackgroundController::OnRootWindowAdded(
     // small screen.
     if (kSmallWallpaperMaxWidth < root_window_size.width() ||
         kSmallWallpaperMaxHeight < root_window_size.height()) {
-      if (current_wallpaper_->is_default_wallpaper) {
-        ReloadDefaultWallpaper();
-      } else {
-        ash::Shell::GetInstance()->user_wallpaper_delegate()->
-            UpdateWallpaper();
-      }
+      current_wallpaper_.reset(NULL);
+      ash::Shell::GetInstance()->user_wallpaper_delegate()->
+          UpdateWallpaper();
     }
   }
 
   InstallDesktopController(root_window);
 }
 
-void DesktopBackgroundController::CacheDefaultWallpaper(int index) {
-  DCHECK(index >= 0);
-
-  WallpaperResolution resolution = GetAppropriateResolution();
-  scoped_refptr<WallpaperOperation> wallpaper_op =
-      new WallpaperOperation(index, resolution);
-  base::WorkerPool::PostTask(
-      FROM_HERE,
-      base::Bind(&WallpaperOperation::Run, wallpaper_op),
-      true);
-}
-
-void DesktopBackgroundController::SetDefaultWallpaper(int index) {
-  // We should not change background when index is invalid. For instance, at
-  // login screen or stub_user login.
-  if (index == GetInvalidWallpaperIndex()) {
-    CreateEmptyWallpaper();
-    return;
-  } else if (index == GetSolidColorIndex()) {
-    SetDesktopBackgroundSolidColorMode(kLoginWallpaperColor);
-    return;
-  }
-
-  // Prevents loading of the same wallpaper as the currently loading/loaded
-  // one.
-  if ((wallpaper_op_.get() && wallpaper_op_->index() == index) ||
-      (current_wallpaper_.get() &&
-       current_wallpaper_->wallpaper_index == index)) {
-    return;
-  }
+void DesktopBackgroundController::SetDefaultWallpaper(
+    const WallpaperInfo& info) {
+  DCHECK_NE(GetWallpaperIDR(), info.idr);
 
   CancelPendingWallpaperOperation();
-
-  WallpaperResolution resolution = GetAppropriateResolution();
-
-  wallpaper_op_ = new WallpaperOperation(index, resolution);
+  wallpaper_loader_ = new WallpaperLoader(info);
   base::WorkerPool::PostTaskAndReply(
       FROM_HERE,
-      base::Bind(&WallpaperOperation::Run, wallpaper_op_),
+      base::Bind(&WallpaperLoader::LoadOnWorkerPoolThread, wallpaper_loader_),
       base::Bind(&DesktopBackgroundController::OnWallpaperLoadCompleted,
                  weak_ptr_factory_.GetWeakPtr(),
-                 wallpaper_op_),
+                 wallpaper_loader_),
       true /* task_is_slow */);
 }
 
-void DesktopBackgroundController::ReloadDefaultWallpaper() {
-  int index = current_wallpaper_->wallpaper_index;
-  current_wallpaper_.reset(NULL);
-  SetDefaultWallpaper(index);
-}
-
 void DesktopBackgroundController::SetCustomWallpaper(
     const gfx::ImageSkia& wallpaper,
     WallpaperLayout layout) {
@@ -240,7 +221,8 @@ void DesktopBackgroundController::SetCustomWallpaper(
     return;
   }
 
-  current_wallpaper_.reset(new WallpaperData(layout, wallpaper));
+  WallpaperInfo info = { -1, layout };
+  current_wallpaper_.reset(new WallpaperData(info, wallpaper));
   FOR_EACH_OBSERVER(DesktopBackgroundControllerObserver, observers_,
                     OnWallpaperDataChanged());
   SetDesktopBackgroundImageMode();
@@ -248,8 +230,8 @@ void DesktopBackgroundController::SetCustomWallpaper(
 
 void DesktopBackgroundController::CancelPendingWallpaperOperation() {
   // Set canceled flag of previous request to skip unneeded loading.
-  if (wallpaper_op_.get())
-    wallpaper_op_->Cancel();
+  if (wallpaper_loader_.get())
+    wallpaper_loader_->Cancel();
 
   // Cancel reply callback for previous request.
   weak_ptr_factory_.InvalidateWeakPtrs();
@@ -270,14 +252,14 @@ void DesktopBackgroundController::CreateEmptyWallpaper() {
 
 WallpaperResolution DesktopBackgroundController::GetAppropriateResolution() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  WallpaperResolution resolution = SMALL;
+  WallpaperResolution resolution = WALLPAPER_RESOLUTION_SMALL;
   Shell::RootWindowList root_windows = Shell::GetAllRootWindows();
   for (Shell::RootWindowList::iterator iter = root_windows.begin();
        iter != root_windows.end(); ++iter) {
     gfx::Size root_window_size = (*iter)->GetHostSize();
     if (root_window_size.width() > kSmallWallpaperMaxWidth ||
         root_window_size.height() > kSmallWallpaperMaxHeight) {
-      resolution = LARGE;
+      resolution = WALLPAPER_RESOLUTION_LARGE;
     }
   }
   return resolution;
@@ -312,15 +294,15 @@ void DesktopBackgroundController::SetDesktopBackgroundImageMode() {
 }
 
 void DesktopBackgroundController::OnWallpaperLoadCompleted(
-    scoped_refptr<WallpaperOperation> wo) {
-  current_wallpaper_.reset(wo->ReleaseWallpaperData());
+    scoped_refptr<WallpaperLoader> wl) {
+  current_wallpaper_.reset(wl->ReleaseWallpaperData());
   FOR_EACH_OBSERVER(DesktopBackgroundControllerObserver, observers_,
                     OnWallpaperDataChanged());
 
   SetDesktopBackgroundImageMode();
 
-  DCHECK(wo.get() == wallpaper_op_.get());
-  wallpaper_op_ = NULL;
+  DCHECK(wl.get() == wallpaper_loader_.get());
+  wallpaper_loader_ = NULL;
 }
 
 void DesktopBackgroundController::NotifyAnimationFinished() {