Prerender Instant search base url on omnibox focus event

chrome/browser/ui/search/search_tab_helper.cc

Index: chrome/browser/ui/search/search_tab_helper.cc
diff --git a/chrome/browser/ui/search/search_tab_helper.cc b/chrome/browser/ui/search/search_tab_helper.cc
index b117ad020d24c398cc3042ed0019dc3e3e713317..9aeaf37f0ab70dea64c7d474c8a652c872460698 100644
--- a/chrome/browser/ui/search/search_tab_helper.cc
+++ b/chrome/browser/ui/search/search_tab_helper.cc
@@ -24,6 +24,7 @@
 #include "chrome/browser/ui/omnibox/omnibox_edit_model.h"
 #include "chrome/browser/ui/omnibox/omnibox_popup_model.h"
 #include "chrome/browser/ui/omnibox/omnibox_view.h"
+#include "chrome/browser/ui/search/instant_search_prerenderer.h"
 #include "chrome/browser/ui/search/search_ipc_router_policy_impl.h"
 #include "chrome/browser/ui/search/search_tab_helper_delegate.h"
 #include "chrome/browser/ui/tab_contents/core_tab_helper.h"
@@ -172,6 +173,24 @@ void SearchTabHelper::OmniboxFocusChanged(OmniboxFocusState state,
   if (web_contents_->GetController().GetPendingEntry() == NULL) {

[Jered, 2014/06/19 21:09:46]

This check makes me worry that there is a case where we might start spinning up
a prerender after the user has selected a match in the omnibox dropdown, since
it seems there are spurious focus change events in that case. It'd be bad to
delay navigation when we know that the user is not going to search. Are you
certain this doesn't happen?

[sidharthms, 2014/06/20 00:31:44]

Done.

     ipc_router_.SetInputInProgress(IsInputInProgress());
   }
+
+  if (chrome::ShouldPrerenderInstantUrlOnOmniboxFocus()) {
+    InstantSearchPrerenderer* prerenderer =
+        InstantSearchPrerenderer::GetForProfile(profile());
+    if (!prerenderer)
+      return;
+
+    if (state == OMNIBOX_FOCUS_NONE) {
+      prerenderer->Cancel();
+      return;
+    }
+
+    if (!IsSearchResultsPage()) {
+      prerenderer->Init(
+          web_contents_->GetController().GetSessionStorageNamespaceMap(),
+          web_contents_->GetContainerBounds().size());
+    }
+  }
 }
 
 void SearchTabHelper::NavigationEntryUpdated() {
@@ -214,6 +233,18 @@ void SearchTabHelper::Submit(const base::string16& text) {
 
 void SearchTabHelper::OnTabActivated() {
   ipc_router_.OnTabActivated();
+
+  OmniboxView* omnibox_view = GetOmniboxView();
+  if (chrome::ShouldPrerenderInstantUrlOnOmniboxFocus() && omnibox_view &&
+      omnibox_view->model()->has_focus()) {
+    InstantSearchPrerenderer* prerenderer =
+        InstantSearchPrerenderer::GetForProfile(profile());
+    if (prerenderer && !IsSearchResultsPage()) {
+      prerenderer->Init(
+          web_contents_->GetController().GetSessionStorageNamespaceMap(),
+          web_contents_->GetContainerBounds().size());
+    }
+  }
 }
 
 void SearchTabHelper::OnTabDeactivated() {