Remove DetermineIfPageSupportsInstant and all its plumbing

chrome/renderer/searchbox/searchbox.cc

Index: chrome/renderer/searchbox/searchbox.cc
diff --git a/chrome/renderer/searchbox/searchbox.cc b/chrome/renderer/searchbox/searchbox.cc
index 179b5315bde9934af38eeaf46cf3079468b81438..f5b8c20a2b1ff4733cfbafe59c74338041ca68cb 100644
--- a/chrome/renderer/searchbox/searchbox.cc
+++ b/chrome/renderer/searchbox/searchbox.cc
@@ -357,13 +357,6 @@ void SearchBox::ChromeIdentityCheckResult(const base::string16& identity,
       render_frame()->GetWebFrame(), identity, identity_match);
 }
 
-void SearchBox::DetermineIfPageSupportsInstant() {
-  bool result = extensions_v8::SearchBoxExtension::PageSupportsInstant(
-      render_frame()->GetWebFrame());
-  DVLOG(1) << render_frame() << " PageSupportsInstant: " << result;
-  instant_service_->InstantSupportDetermined(page_seq_no_, result);
-}
-
 void SearchBox::FocusChanged(OmniboxFocusState new_focus_state,
                              OmniboxFocusChangeReason reason) {
   bool key_capture_enabled = new_focus_state == OMNIBOX_FOCUS_INVISIBLE;