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

chrome/browser/instant/instant_tab.cc

Index: chrome/browser/instant/instant_tab.cc
diff --git a/chrome/browser/instant/instant_tab.cc b/chrome/browser/instant/instant_tab.cc
index 82870cfd437e622566799c8c062080e6afef4cd9..f9166d35f70a492519c2729745c8a0a7969f72e2 100644
--- a/chrome/browser/instant/instant_tab.cc
+++ b/chrome/browser/instant/instant_tab.cc
@@ -87,3 +87,8 @@ void InstantTab::RenderViewGone() {
 void InstantTab::AboutToNavigateMainFrame(const GURL& url) {
   // The client is a committed tab, navigations will happen as expected.
 }
+
+void InstantTab::NavigateToURL(const GURL& url,
+                               content::PageTransition transition) {
+  controller_->NavigateToURL(url, transition);
+}