Don't allow sending data URLs to WebUI, unless in a ChromeOS BalloonHost.

content/public/browser/web_contents_delegate.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 CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_DELEGATE_H_
 #pragma once
 
 #include <set>
 #include <string>
@@ skipping 139 matching lines @@
                                   const gfx::Point& location,
                                   bool motion) {}
 
   // Request the delegate to change the zoom level of the current tab.
   virtual void ContentsZoomChange(bool zoom_in) {}
 
   // Check whether this contents is inside a window dedicated to running a web
   // application.
   virtual bool IsApplication() const;
 
+  // Check whether this contents is permitted to load data URLs in WebUI mode.
+  // This is normally disallowed for security.
+  virtual bool CanLoadDataURLsInWebUI() const;
+
   // Detach the given tab and convert it to a "webapp" view.  The tab must be
   // a WebContents with a valid WebApp set.
   virtual void ConvertContentsToApplication(WebContents* source) {}
 
   // Whether the specified tab can be reloaded.
   // Reloading can be disabled e. g. for the DevTools window.
   virtual bool CanReloadContents(WebContents* source) const;
 
   // Return the rect where to display the resize corner, if any, otherwise
   // an empty rect.
@@ skipping 247 matching lines @@
   // Called when |this| is no longer the WebContentsDelegate for |source|.
   void Detach(WebContents* source);
 
   // The WebContents that this is currently a delegate for.
   std::set<WebContents*> attached_contents_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_DELEGATE_H_