Convert NavigationMetricsRecorder to use the new navigation callbacks.

content/browser/frame_host/navigation_handle_impl.h

Index: content/browser/frame_host/navigation_handle_impl.h
diff --git a/content/browser/frame_host/navigation_handle_impl.h b/content/browser/frame_host/navigation_handle_impl.h
index 279c45977f11f54826448381cc86351d1f125bae..362e87422db978b4c59538a08abd2839f78f5c63 100644
--- a/content/browser/frame_host/navigation_handle_impl.h
+++ b/content/browser/frame_host/navigation_handle_impl.h
@@ -111,6 +111,7 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   bool IsSamePage() override;
   bool HasCommitted() override;
   bool IsErrorPage() override;
+  const GURL& GetPreviousURL() override;
   const net::HttpResponseHeaders* GetResponseHeaders() override;
   net::HttpResponseInfo::ConnectionInfo GetConnectionInfo() override;
   void Resume() override;
@@ -279,6 +280,7 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   void DidCommitNavigation(
       const FrameHostMsg_DidCommitProvisionalLoad_Params& params,
       bool same_page,
+      const GURL& previous_url,
       RenderFrameHostImpl* render_frame_host);
 
   // Called during commit. Takes ownership of the embedder's NavigationData
@@ -458,6 +460,8 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   GURL searchable_form_url_;
   std::string searchable_form_encoding_;
 
+  GURL previous_url_;
+
   base::WeakPtrFactory<NavigationHandleImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationHandleImpl);