Allow override of user agent depending on url.

content/public/renderer/content_renderer_client.h

Index: content/public/renderer/content_renderer_client.h
diff --git a/content/public/renderer/content_renderer_client.h b/content/public/renderer/content_renderer_client.h
index 55db98c4cb1e8dfe5c65c8c635aebf4a4b0dfa35..698e643cb6c6e374f8f5b819dd69d82c2fcf546f 100644
--- a/content/public/renderer/content_renderer_client.h
+++ b/content/public/renderer/content_renderer_client.h
@@ -273,6 +273,10 @@ class CONTENT_EXPORT ContentRendererClient {
 
   // Returns true if dev channel APIs are available for plugins.
   virtual bool IsPluginAllowedToUseDevChannelAPIs();
+
+  // Returns a user agent override specific for |url|, or empty string if
+  // default user agent should be used.
+  virtual std::string GetUserAgentOverrideForURL(const GURL& url);
 };
 
 }  // namespace content