Specify AllowCaching = false for dynamically-generated contents

chrome/browser/ui/webui/extensions/extension_icon_source.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_EXTENSIONS_EXTENSION_ICON_SOURCE_H_
 #define CHROME_BROWSER_UI_WEBUI_EXTENSIONS_EXTENSION_ICON_SOURCE_H_
 
 #include <map>
 #include <string>
 
@@ skipping 55 matching lines @@
   // by |resource_id|.
   static SkBitmap* LoadImageByResourceId(int resource_id);
 
   // content::URLDataSource implementation.
   std::string GetSource() const override;
   std::string GetMimeType(const std::string&) const override;
   void StartDataRequest(
       const std::string& path,
       const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
       const content::URLDataSource::GotDataCallback& callback) override;
+  bool AllowCaching() const override;
 
  private:
   // Encapsulates the request parameters for |request_id|.
   struct ExtensionIconRequest;
 
   ~ExtensionIconSource() override;
 
   // Returns the bitmap for the default app image.
   const SkBitmap* GetDefaultAppImage();
 
@@ skipping 67 matching lines @@
   std::unique_ptr<SkBitmap> default_extension_data_;
 
   base::CancelableTaskTracker cancelable_task_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionIconSource);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_UI_WEBUI_EXTENSIONS_EXTENSION_ICON_SOURCE_H_