Add new IPC for searchbox to pipe SearchBox NavigateContentWindow calls to the browser.

chrome/browser/instant/instant_client.h

Index: chrome/browser/instant/instant_client.h
diff --git a/chrome/browser/instant/instant_client.h b/chrome/browser/instant/instant_client.h
index 821c36cd8f5c2733ade73222b000f6ea4e2ab7c1..461683c2deb538eb86d8956774b51d1bb539b65e 100644
--- a/chrome/browser/instant/instant_client.h
+++ b/chrome/browser/instant/instant_client.h
@@ -64,6 +64,9 @@ class InstantClient : public content::WebContentsObserver {
     // Called when the page is about to navigate.
     virtual void AboutToNavigateMainFrame(const GURL& url) = 0;
 
+    // Called when the SearchBox wants to navigate to the specified URL.
+    virtual void NavigateToURL(const GURL& url) = 0;
+
    protected:
     virtual ~Delegate();
   };
@@ -146,6 +149,7 @@ class InstantClient : public content::WebContentsObserver {
                           InstantSizeUnits units);
   void StartCapturingKeyStrokes(int page_id);
   void StopCapturingKeyStrokes(int page_id);
+  void SearchBoxNavigate(int page_id, const GURL& url);
 
   Delegate* const delegate_;