[New Tab Page] Change the mechanism to intercept online NTP errors

chrome/browser/profiles/profile_io_data.h

Index: chrome/browser/profiles/profile_io_data.h
diff --git a/chrome/browser/profiles/profile_io_data.h b/chrome/browser/profiles/profile_io_data.h
index 23ce4348586d44130a396c5003d265c4baa8065d..297889bcaad6f5dce8c9d4afb3cb56fa47b976f8 100644
--- a/chrome/browser/profiles/profile_io_data.h
+++ b/chrome/browser/profiles/profile_io_data.h
@@ -28,6 +28,7 @@
 #include "net/http/http_cache.h"
 #include "net/http/http_network_session.h"
 #include "net/url_request/url_request_context.h"
+#include "net/url_request/url_request_interceptor.h"
 #include "net/url_request/url_request_job_factory.h"
 
 class ChromeHttpUserAgentSettings;
@@ -316,6 +317,10 @@ class ProfileIOData {
     scoped_ptr<ProtocolHandlerRegistry::JobInterceptorFactory>
         protocol_handler_interceptor;
 
+    // Holds the URLRequestInterceptor pointer that is created on the UI thread
+    // and then passed to the list of request_interceptors on the IO thread.
+    scoped_ptr<net::URLRequestInterceptor> new_tab_page_interceptor;
+
     // We need to initialize the ProxyConfigService from the UI thread
     // because on linux it relies on initializing things through gconf,
     // and needs to be on the main thread.