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 d01af5d992390385c60bd3bfa0da63f82dd122ff..584d82125c04e3a723973091512a46bddd5b1011 100644
--- a/chrome/browser/ui/search/instant_controller.cc
+++ b/chrome/browser/ui/search/instant_controller.cc
@@ -1248,6 +1248,15 @@ void InstantController::InstantPageRenderViewCreated(
   UpdateMostVisitedItems();
 }
 
+void InstantController::InstantSupportChanged(
+    const content::WebContents* contents,
+    InstantSupportState instant_support) {
+  if (instant_support == INSTANT_SUPPORT_UNKNOWN)

[samarth, 2013/06/18 22:03:36]

I don't think this is right either because now we never call ResetInstantTab.

I thought about it more and here's what makes the most sense to me:
if (instant_support == INSTANT_SUPPORT_YES)
  ResetInstantTab();

and that's it. I'd also add a comment explaining that the other cases are
already handled by the listener in InstantPage, but that we need to listen for
support becoming YES here because InstantPage is not hooked up to the active tab
in that case.

[kmadhusu, 2013/06/18 23:22:56]

Done.

+    return;
+
+  InstantSupportDetermined(contents, instant_support == INSTANT_SUPPORT_YES);
+}
+
 void InstantController::InstantSupportDetermined(
     const content::WebContents* contents,
     bool supports_instant) {