If customization includes default wallpaper, download and apply it.

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 7673f29aa6a48d9439e9397c4663105e09f001b3..92f4b705fdda8df0e937f1a98a2bf35339ff49b0 100644
--- a/ash/desktop_background/desktop_background_controller.cc
+++ b/ash/desktop_background/desktop_background_controller.cc
@@ -155,8 +155,7 @@ class DesktopBackgroundController::WallpaperLoader
 };
 
 DesktopBackgroundController::DesktopBackgroundController()
-    : command_line_for_testing_(NULL),
-      locked_(false),
+    : locked_(false),
       desktop_background_mode_(BACKGROUND_NONE),
       current_default_wallpaper_resource_id_(-1),
       weak_ptr_factory_(this),
@@ -208,30 +207,23 @@ void DesktopBackgroundController::OnRootWindowAdded(aura::Window* root_window) {
   InstallDesktopController(root_window);
 }
 
-bool DesktopBackgroundController::SetDefaultWallpaper(bool is_guest) {
-  VLOG(1) << "SetDefaultWallpaper: is_guest=" << is_guest;
+bool DesktopBackgroundController::SetDefaultWallpaper(
+    const base::FilePath& small_resolution_path,
+    const base::FilePath& large_resolution_path) {
+  VLOG(1) << "SetDefaultWallpaper: small_resolution_path='"
+          << small_resolution_path.value() << "' large_resolution_path='"
+          << large_resolution_path.value() << "'";
   const bool use_large =
       GetAppropriateResolution() == WALLPAPER_RESOLUTION_LARGE;
 
-  base::FilePath file_path;
-  WallpaperLayout file_layout = use_large ? WALLPAPER_LAYOUT_CENTER_CROPPED :
-      WALLPAPER_LAYOUT_CENTER;
-  int resource_id = use_large ? IDR_AURA_WALLPAPER_DEFAULT_LARGE :
-      IDR_AURA_WALLPAPER_DEFAULT_SMALL;
+  const base::FilePath& file_path =
+      use_large ? large_resolution_path : small_resolution_path;
+  WallpaperLayout file_layout =
+      use_large ? WALLPAPER_LAYOUT_CENTER_CROPPED : WALLPAPER_LAYOUT_CENTER;
+  int resource_id = use_large ? IDR_AURA_WALLPAPER_DEFAULT_LARGE
+                              : IDR_AURA_WALLPAPER_DEFAULT_SMALL;
   WallpaperLayout resource_layout = WALLPAPER_LAYOUT_TILE;
 
-  CommandLine* command_line = command_line_for_testing_ ?
-      command_line_for_testing_ : CommandLine::ForCurrentProcess();
-  const char* switch_name = NULL;
-  if (is_guest) {
-    switch_name = use_large ? switches::kAshGuestWallpaperLarge :
-        switches::kAshGuestWallpaperSmall;
-  } else {
-    switch_name = use_large ? switches::kAshDefaultWallpaperLarge :
-        switches::kAshDefaultWallpaperSmall;
-  }
-  file_path = command_line->GetSwitchValuePath(switch_name);
-
   if (DefaultWallpaperIsAlreadyLoadingOrLoaded(file_path, resource_id)) {
     VLOG(1) << "Default wallpaper is already loading or loaded";
     return false;
@@ -328,6 +320,18 @@ void DesktopBackgroundController::OnDisplayConfigurationChanged() {
   }
 }
 
+// Do not forget to update DefaultWallpaperIsAlreadyLoadingOrLoaded on change!
+bool DesktopBackgroundController::DefaultWallpaperFileIsAlreadyLoadingOrLoaded(

[Daniel Erat, 2014/03/25 18:32:54]

i'm sorry, but i still don't understand why you need this method. can you
describe the specific sequence of events that you're concerned wouldn't be
handled correctly if you use the existing method that additionally checks the
resource ID?

[Alexander Alekseev, 2014/03/25 19:09:33]

It will work with existing method, but I will have to call it in
WallpaperManager like:

const bool need_reset =
      DefaultWallpaperIsAlreadyLoadingOrLoaded(
          default_small_wallpaper_file_,
          IDR_AURA_WALLPAPER_DEFAULT_SMALL) ||
     DefaultWallpaperIsAlreadyLoadingOrLoaded(
          default_large_wallpaper_file_,
          IDR_AURA_WALLPAPER_DEFAULT_LARGE);

So the idea was not to expose IDR_AURA_* constants (and DBC implementation
details) outside of ash:: . If you think it's OK, I can reuse existing.

+    const base::FilePath& image_file) const {
+  return (default_wallpaper_loader_.get() &&
+          !default_wallpaper_loader_->IsCanceled() &&
+          default_wallpaper_loader_->file_path() == image_file) ||
+         (current_wallpaper_.get() &&
+          current_default_wallpaper_path_ == image_file);
+}
+
+// Do not forget to update DefaultWallpaperFileIsAlreadyLoadingOrLoaded
+// on change!
 bool DesktopBackgroundController::DefaultWallpaperIsAlreadyLoadingOrLoaded(
     const base::FilePath& image_file,
     int image_resource_id) const {