Convert GuestViewBase to use the new navigation callbacks.

components/guest_view/browser/guest_view_base.h

Index: components/guest_view/browser/guest_view_base.h
diff --git a/components/guest_view/browser/guest_view_base.h b/components/guest_view/browser/guest_view_base.h
index 6c58eeff981eaefd0e0303b169ccde7423e07e85..05a6843b4106c4d52568264e246429a16748f78a 100644
--- a/components/guest_view/browser/guest_view_base.h
+++ b/components/guest_view/browser/guest_view_base.h
@@ -230,9 +230,8 @@ class GuestViewBase : public content::BrowserPluginGuestDelegate,
                  bool final_update) override;
 
   // WebContentsObserver implementation.
-  void DidNavigateMainFrame(
-      const content::LoadCommittedDetails& details,
-      const content::FrameNavigateParams& params) override;
+  void DidFinishNavigation(
+      content::NavigationHandle* navigation_handle) override;
 
   // Given a set of initialization parameters, a concrete subclass of
   // GuestViewBase can create a specialized WebContents that it returns back to