Allow default font size changing on Linux.

content/public/common/renderer_preferences.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.
 //
 // A struct for managing browser's settings that apply to the renderer or its
 // webview.  These differ from WebPreferences since they apply to Chromium's
 // glue layer rather than applying to just WebKit.
 //
 // Adding new values to this class probably involves updating
 // common/view_messages.h, browser/browser.cc, etc.
@@ skipping 108 matching lines @@
   // Disables rendering default error page when client choses to block a page.
   // Corresponds to net::ERR_BLOCKED_BY_CLIENT.
   bool disable_client_blocked_error_page;
 
   // Determines whether plugins are allowed to enter fullscreen mode.
   bool plugin_fullscreen_allowed;
 
   // Whether video-overlay (hole-punching) should be used for the embedded
   // encrypted video.  Currently only used by Android.
   bool use_video_overlay_for_embedded_encrypted_video;
+
+  // The default font size used for rendering on Linux.
+  int default_font_size;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_COMMON_RENDERER_PREFERENCES_H_