Set user_gesture bit at NavigationHandle creation time.

content/browser/frame_host/navigator.h

Index: content/browser/frame_host/navigator.h
diff --git a/content/browser/frame_host/navigator.h b/content/browser/frame_host/navigator.h
index 9f29e553ea797722de94db4e8d4a1d4cc8c0f32b..1025f7be5d5a2adab692ddfaeff2528c55405eea 100644
--- a/content/browser/frame_host/navigator.h
+++ b/content/browser/frame_host/navigator.h
@@ -49,10 +49,10 @@ class CONTENT_EXPORT Navigator : public base::RefCounted<Navigator> {
   // Notifications coming from the RenderFrameHosts ----------------------------
 
   // The RenderFrameHostImpl started a provisional load.
-  virtual void DidStartProvisionalLoad(
-      RenderFrameHostImpl* render_frame_host,
-      const GURL& url,
-      const base::TimeTicks& navigation_start) {};
+  virtual void DidStartProvisionalLoad(RenderFrameHostImpl* render_frame_host,
+                                       const GURL& url,
+                                       const base::TimeTicks& navigation_start,
+                                       NavigationGesture gesture){};
 
   // The RenderFrameHostImpl has failed a provisional load.
   virtual void DidFailProvisionalLoadWithError(