Revert changes to have ExtensionService notify ThemeService directly for themes

chrome/browser/ui/gtk/gtk_theme_service.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 "chrome/browser/ui/gtk/gtk_theme_service.h"
 
 #include <gtk/gtk.h>
 
 #include <set>
 #include <string>
@@ skipping 318 matching lines @@
   return ThemeService::GetColor(id);
 }
 
 bool GtkThemeService::HasCustomImage(int id) const {
   if (use_gtk_)
     return IsOverridableImage(id);
 
   return ThemeService::HasCustomImage(id);
 }
 
-void GtkThemeService::InitThemesFor(content::NotificationObserver* observer) {
+void GtkThemeService::InitThemesFor(NotificationObserver* observer) {
   observer->Observe(chrome::NOTIFICATION_BROWSER_THEME_CHANGED,
                     content::Source<ThemeService>(this),
                     content::NotificationService::NoDetails());
 }
 
 void GtkThemeService::SetTheme(const extensions::Extension* extension) {
   profile()->GetPrefs()->SetBoolean(prefs::kUsesSystemTheme, false);
   LoadDefaultValues();
   ThemeService::SetTheme(extension);
 }
@@ skipping 793 matching lines @@
   cairo_stroke(cr);
   cairo_destroy(cr);
   cairo_pattern_destroy(pattern);
 
   return TRUE;
 }
 
 void GtkThemeService::OnUsesSystemThemeChanged() {
   use_gtk_ = profile()->GetPrefs()->GetBoolean(prefs::kUsesSystemTheme);
 }