Add error description to the DidFailProvisionalLoad callback.

content/browser/tab_contents/tab_contents_observer.cc

Index: content/browser/tab_contents/tab_contents_observer.cc
diff --git a/content/browser/tab_contents/tab_contents_observer.cc b/content/browser/tab_contents/tab_contents_observer.cc
index f3b5af524336704b7aba447ea3ef8c4ceb146a7c..76207a3b13e52b3ab50b2230387ba5e46ea409f3 100644
--- a/content/browser/tab_contents/tab_contents_observer.cc
+++ b/content/browser/tab_contents/tab_contents_observer.cc
@@ -46,10 +46,12 @@ void TabContentsObserver::DidCommitProvisionalLoadForFrame(
     PageTransition::Type transition_type) {
 }
 
-void TabContentsObserver::DidFailProvisionalLoad(int64 frame_id,
-                                                 bool is_main_frame,
-                                                 const GURL& validated_url,
-                                                 int error_code) {
+void TabContentsObserver::DidFailProvisionalLoad(
+    int64 frame_id,
+    bool is_main_frame,
+    const GURL& validated_url,
+    int error_code,
+    const string16& error_description) {
 }
 
 void TabContentsObserver::DocumentLoadedInFrame(int64 frame_id) {