Prerender Instant search base url on omnibox focus event

chrome/browser/ui/search/search_tab_helper.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/search/search_tab_helper.h"
 
 #include <set>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_util.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/history/most_visited_tiles_experiment.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/instant_service.h"
 #include "chrome/browser/search/instant_service_factory.h"
 #include "chrome/browser/search/search.h"
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/browser/ui/app_list/app_list_util.h"
 #include "chrome/browser/ui/browser_navigator.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/omnibox/location_bar.h"
 #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"
 #include "chrome/browser/ui/webui/ntp/ntp_user_data_logger.h"
 #include "chrome/common/url_constants.h"
 #include "components/signin/core/browser/signin_manager.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/navigation_type.h"
@@ skipping 125 matching lines @@
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_OMNIBOX_FOCUS_CHANGED,
       content::Source<SearchTabHelper>(this),
       content::NotificationService::NoDetails());
 
   ipc_router_.OmniboxFocusChanged(state, reason);
 
   // Don't send oninputstart/oninputend updates in response to focus changes
   // if there's a navigation in progress. This prevents Chrome from sending
   // a spurious oninputend when the user accepts a match in the omnibox.
   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() {
   if (!is_search_enabled_)
     return;
 
   UpdateMode(false, false);
 }
 
 void SearchTabHelper::InstantSupportChanged(bool instant_support) {
@@ skipping 22 matching lines @@
     const InstantSuggestion& suggestion) {
   ipc_router_.SetSuggestionToPrefetch(suggestion);
 }
 
 void SearchTabHelper::Submit(const base::string16& text) {
   ipc_router_.Submit(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() {
   ipc_router_.OnTabDeactivated();
 }
 
 void SearchTabHelper::ToggleVoiceSearch() {
   ipc_router_.ToggleVoiceSearch();
 }
 
@@ skipping 360 matching lines @@
 
 bool SearchTabHelper::IsInputInProgress() const {
   OmniboxView* omnibox = GetOmniboxView();
   return !model_.mode().is_ntp() && omnibox &&
       omnibox->model()->focus_state() == OMNIBOX_FOCUS_VISIBLE;
 }
 
 OmniboxView* SearchTabHelper::GetOmniboxView() const {
   return delegate_ ? delegate_->GetOmniboxView() : NULL;
 }