Make URLDataSource::GetSource() const.

chrome/browser/ui/webui/app_launcher_page_ui.h

 // Copyright (c) 2013 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_APP_LAUNCHER_PAGE_UI_H_
 #define CHROME_BROWSER_UI_WEBUI_APP_LAUNCHER_PAGE_UI_H_
 
 #include "content/public/browser/url_data_source.h"
 #include "content/public/browser/web_ui_controller.h"
 #include "ui/base/layout.h"
@@ skipping 13 matching lines @@
   static base::RefCountedMemory* GetFaviconResourceBytes(
       ui::ScaleFactor scale_factor);
 
  private:
   class HTMLSource : public content::URLDataSource {
    public:
     explicit HTMLSource(Profile* profile);
     virtual ~HTMLSource();
 
     // content::URLDataSource implementation.
-    virtual std::string GetSource() OVERRIDE;
+    virtual std::string GetSource() const OVERRIDE;
     virtual void StartDataRequest(
         const std::string& path,
         bool is_incognito,
         const content::URLDataSource::GotDataCallback& callback) OVERRIDE;
     virtual std::string GetMimeType(const std::string&) const OVERRIDE;
     virtual bool ShouldReplaceExistingSource() const OVERRIDE;
     virtual bool ShouldAddContentSecurityPolicy() const OVERRIDE;
 
    private:
 
     // Pointer back to the original profile.
     Profile* profile_;
 
     DISALLOW_COPY_AND_ASSIGN(HTMLSource);
   };
 
   Profile* GetProfile() const;
 
   DISALLOW_COPY_AND_ASSIGN(AppLauncherPageUI);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_APP_LAUNCHER_PAGE_UI_H_