Use a #fefefe solid color wallpaper background before user login for GAIA login flow

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 5994bf2326736021607071c81c048edc2cb3a8ed..ff6bcda3c02bc2543ec40057fb7c7c64297ce04b 100644
--- a/ash/desktop_background/desktop_background_controller.cc
+++ b/ash/desktop_background/desktop_background_controller.cc
@@ -139,6 +139,9 @@ void DesktopBackgroundController::SetLoggedInUserWallpaper() {
   if (index == ash::GetInvalidWallpaperIndex()) {
     CreateEmptyWallpaper();
     return;
+  } else if (index == ash::GetSolidColorIndex()) {

[Nikita (slow), 2012/06/04 18:23:03]

I'm a bit confused why this happens inside SetLoggedInUserWallpaper() method.

Comment says
  // Loads logged in user wallpaper asynchronously and sets to current wallpaper
  // after loaded.

Given the fact that this now handles any wallpaper related initialization on
boot (both normal boot + after crash), makes sense to rename this method to
something like InitializeWallpaper?

[bshe, 2012/06/08 15:06:30]

It is also used when user toggle background color mode in
ash/accelerators/accelerator_controller.cc:163. But I agree rename it to
InitializeWallpaper makes more sense.

On 2012/06/04 18:23:03, Nikita Kostylev wrote:

+    SetDesktopBackgroundSolidColorMode();
+    return;
   }
 
   SetDefaultWallpaper(index);
@@ -150,7 +153,7 @@ void DesktopBackgroundController::SetDesktopBackgroundSolidColorMode() {
   // viewport when there are regions not covered by a layer:
   // http://crbug.com/113445
   ui::Layer* background_layer = new ui::Layer(ui::LAYER_SOLID_COLOR);
-  background_layer->SetColor(SK_ColorBLACK);
+  background_layer->SetColor(SK_ColorWallpaperGray);

[Nikita (slow), 2012/06/04 18:23:03]

I think that it makes sense to pass color as a parameter.

[bshe, 2012/06/08 15:06:30]

Done.

   root_window_->GetChildById(
       internal::kShellWindowId_DesktopBackgroundContainer)->
       layer()->Add(background_layer);