Move instant support to SearchTabHelper.

chrome/browser/ui/search/instant_controller.cc

Index: chrome/browser/ui/search/instant_controller.cc
diff --git a/chrome/browser/ui/search/instant_controller.cc b/chrome/browser/ui/search/instant_controller.cc
index c861a1c963ed4ba3eedc309720e62e8b417164da..fe1cc1bd45c2eada466250960fd566e6f61aa770 100644
--- a/chrome/browser/ui/search/instant_controller.cc
+++ b/chrome/browser/ui/search/instant_controller.cc
@@ -1253,6 +1253,17 @@ void InstantController::InstantPageRenderViewCreated(
   UpdateMostVisitedItems();
 }
 
+void InstantController::InstantSupportChanged(
+    InstantSupportState instant_support) {
+  // Handle INSTANT_SUPPORT_YES here because InstantPage is not hooked up to the
+  // active tab. Search model changed listener in InstantPage will handle other
+  // cases.
+  if (instant_support != INSTANT_SUPPORT_YES)
+    return;
+
+  ResetInstantTab();
+}
+
 void InstantController::InstantSupportDetermined(
     const content::WebContents* contents,
     bool supports_instant) {