Add custom default theme support and create a managed user default theme.

chrome/browser/themes/theme_service.h

Index: chrome/browser/themes/theme_service.h
diff --git a/chrome/browser/themes/theme_service.h b/chrome/browser/themes/theme_service.h
index b6d88696267ebb318459f68a2acea6dd0b853c27..8bbdc84047b74494e36b8350268ab1ad97af5452 100644
--- a/chrome/browser/themes/theme_service.h
+++ b/chrome/browser/themes/theme_service.h
@@ -19,6 +19,7 @@
 #include "content/public/browser/notification_registrar.h"
 #include "ui/base/theme_provider.h"
 
+class CustomThemeProvider;
 class BrowserThemePack;
 class ThemeServiceTest;
 class ThemeSyncableService;
@@ -104,6 +105,10 @@ class ThemeService : public base::NonThreadSafe,
   // ExtensionService.
   virtual void SetTheme(const extensions::Extension* extension);
 
+  // Set a custom default theme instead of the normal default theme.
+  virtual void SetCustomDefaultTheme(
+      scoped_refptr<CustomThemeProvider> theme_provider);
+
   // Reset the theme to default.
   virtual void UseDefaultTheme();
 
@@ -167,6 +172,10 @@ class ThemeService : public base::NonThreadSafe,
 
   void set_ready() { ready_ = true; }
 
+  const CustomThemeProvider* GetThemeProvider() const {
+    return theme_provider_.get();
+  }
+
  private:
   friend class ThemeServiceTest;
 
@@ -215,7 +224,7 @@ class ThemeService : public base::NonThreadSafe,
   // ThemeSource no longer uses the ThemeService when it is not ready.
   bool ready_;
 
-  scoped_refptr<BrowserThemePack> theme_pack_;
+  scoped_refptr<CustomThemeProvider> theme_provider_;
 
   // The number of infobars currently displayed.
   int number_of_infobars_;