Convert SearchTabHelper to use the new navigation callbacks.

chrome/browser/ui/search/search_tab_helper.h

Index: chrome/browser/ui/search/search_tab_helper.h
diff --git a/chrome/browser/ui/search/search_tab_helper.h b/chrome/browser/ui/search/search_tab_helper.h
index 96c5add0f2f817f0f7d862d468781b1cb9beb237..5833c43dbb260487d4c35812eda230f8d6f6e8c3 100644
--- a/chrome/browser/ui/search/search_tab_helper.h
+++ b/chrome/browser/ui/search/search_tab_helper.h
@@ -123,12 +123,10 @@ class SearchTabHelper : public content::WebContentsObserver,
   explicit SearchTabHelper(content::WebContents* web_contents);
 
   // Overridden from contents::WebContentsObserver:
-  void DidStartNavigationToPendingEntry(
-      const GURL& url,
-      content::ReloadType reload_type) override;
-  void DidNavigateMainFrame(
-      const content::LoadCommittedDetails& details,
-      const content::FrameNavigateParams& params) override;
+  void DidStartNavigation(
+      content::NavigationHandle* navigation_handle) override;
+  void DidFinishNavigation(
+      content::NavigationHandle* navigation_handle) override;
   void DidFinishLoad(content::RenderFrameHost* render_frame_host,
                      const GURL& validated_url) override;
   void NavigationEntryCommitted(