Modified components ui to address concern of all the time disabled check update button.

chrome/browser/ui/webui/components_ui.h

Index: chrome/browser/ui/webui/components_ui.h
diff --git a/chrome/browser/ui/webui/components_ui.h b/chrome/browser/ui/webui/components_ui.h
index 2e98f211a2070adcbef2c7ba29035aa0626a19f1..d215b9a3bb07e312ed1cdcf932704bdc05d8ed6f 100644
--- a/chrome/browser/ui/webui/components_ui.h
+++ b/chrome/browser/ui/webui/components_ui.h
@@ -5,6 +5,8 @@
 #ifndef CHROME_BROWSER_UI_WEBUI_COMPONENTS_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_COMPONENTS_UI_H_
 
+#include "chrome/browser/component_updater/component_updater_service.h"
+#include "chrome/browser/component_updater/crx_update_item.h"
 #include "content/public/browser/web_ui_controller.h"
 #include "ui/base/layout.h"
 
@@ -16,16 +18,26 @@ namespace user_prefs {
 class PrefRegistrySyncable;
 }
 
-class ComponentsUI : public content::WebUIController {
+class ComponentsUI : public content::WebUIController,
+                     public component_updater::ServiceObserver {
  public:
   explicit ComponentsUI(content::WebUI* web_ui);
+  virtual ~ComponentsUI();
 
   static void OnDemandUpdate(const std::string& component_id);
 
+  static base::ListValue* LoadComponents();
+
   static base::RefCountedMemory* GetFaviconResourceBytes(
       ui::ScaleFactor scale_factor);
 
+  // ServiceObserver implementation.
+  virtual void OnEvent(Events event, const std::string& id) OVERRIDE;
+
  private:
+  static base::string16 ComponentEventToString(Events event);
+  static base::string16 ServiceStatusToString(
+      component_updater::CrxUpdateItem::Status status);
   DISALLOW_COPY_AND_ASSIGN(ComponentsUI);
 };