[cleanup] Use Delegate method to control context menu and eliminate HtmlDialogWithoutContextMenuView

chrome/browser/chromeos/login/login_html_dialog.h

Index: chrome/browser/chromeos/login/login_html_dialog.h
diff --git a/chrome/browser/chromeos/login/login_html_dialog.h b/chrome/browser/chromeos/login/login_html_dialog.h
index 6b3112b39ffd17c3c8f328c6ecc9740d9e69ad56..4fd095322ef18a539cab251b7a6ed2bba64c473d 100644
--- a/chrome/browser/chromeos/login/login_html_dialog.h
+++ b/chrome/browser/chromeos/login/login_html_dialog.h
@@ -55,16 +55,18 @@ class LoginHtmlDialog : public HtmlDialogUIDelegate,
 
  protected:
   // HtmlDialogUIDelegate implementation.
-  virtual bool IsDialogModal() const;
-  virtual std::wstring GetDialogTitle() const;
-  virtual GURL GetDialogContentURL() const;
+  virtual bool IsDialogModal() const OVERRIDE;
+  virtual std::wstring GetDialogTitle() const OVERRIDE;
+  virtual GURL GetDialogContentURL() const OVERRIDE;
   virtual void GetWebUIMessageHandlers(
-      std::vector<WebUIMessageHandler*>* handlers) const;
-  virtual void GetDialogSize(gfx::Size* size) const;
-  virtual std::string GetDialogArgs() const;
-  virtual void OnDialogClosed(const std::string& json_retval);
-  virtual void OnCloseContents(TabContents* source, bool* out_close_dialog);
-  virtual bool ShouldShowDialogTitle() const;
+      std::vector<WebUIMessageHandler*>* handlers) const OVERRIDE;
+  virtual void GetDialogSize(gfx::Size* size) const OVERRIDE;
+  virtual std::string GetDialogArgs() const OVERRIDE;
+  virtual void OnDialogClosed(const std::string& json_retval) OVERRIDE;
+  virtual void OnCloseContents(
+      TabContents* source, bool* out_close_dialog) OVERRIDE;
+  virtual bool ShouldShowDialogTitle() const OVERRIDE;
+  virtual bool HandleContextMenu(const ContextMenuParams& params) OVERRIDE;
 
   // NotificationObserver implementation.
   virtual void Observe(NotificationType type,