Move instant support to SearchTabHelper.

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 "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/search.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
+#include "content/public/browser/web_contents.h"
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(SearchTabHelper);
 
 namespace {
 
 bool IsNTP(const content::WebContents* contents) {
   // We can't use WebContents::GetURL() because that uses the active entry,
   // whereas we want the visible entry.
   const content::NavigationEntry* entry =
       contents->GetController().GetVisibleEntry();
   if (entry && entry->GetVirtualURL() == GURL(chrome::kChromeUINewTabURL))
     return true;
 
   return chrome::IsInstantNTP(contents);
 }
 
 bool IsSearchResults(const content::WebContents* contents) {
   return !chrome::GetSearchTerms(contents).empty();
 }
 
+// TODO(kmadhusu): Move this helper from anonymous namespace to chrome
+// namespace and remove InstantPage::IsLocal().
+bool IsLocal(const content::WebContents* contents) {
+  return contents &&
+      (contents->GetURL() == GURL(chrome::kChromeSearchLocalNtpUrl) ||
+       contents->GetURL() == GURL(chrome::kChromeSearchLocalGoogleNtpUrl));
+}
+
 }  // namespace
 
 SearchTabHelper::SearchTabHelper(content::WebContents* web_contents)
     : WebContentsObserver(web_contents),
       is_search_enabled_(chrome::IsInstantExtendedAPIEnabled()),
       user_input_in_progress_(false),
       popup_is_open_(false),
       user_text_is_empty_(true),
       web_contents_(web_contents) {
   if (!is_search_enabled_)
@@ skipping 25 matching lines @@
   UpdateMode();
 }
 
 void SearchTabHelper::NavigationEntryUpdated() {
   if (!is_search_enabled_)
     return;
 
   UpdateMode();
 }
 
+void SearchTabHelper::InstantSupportChanged(bool supports_instant) {
+  if (!is_search_enabled_)
+    return;
+
+  model_.SetSupportsInstant(supports_instant);
+}
+
 void SearchTabHelper::Observe(
     int type,
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
   DCHECK_EQ(content::NOTIFICATION_NAV_ENTRY_COMMITTED, type);
   UpdateMode();
 }
 
 bool SearchTabHelper::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(SearchTabHelper, message)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_SearchBoxShowBars,
                         OnSearchBoxShowBars)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_SearchBoxHideBars,
                         OnSearchBoxHideBars)
+    IPC_MESSAGE_HANDLER(ChromeViewHostMsg_InstantSupportDetermined,
+                        OnInstantSupportDetermined)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
+void SearchTabHelper::DidFinishLoad(
+    int64 /* frame_id */,
+    const GURL& /* validated_url */,
+    bool is_main_frame,
+    content::RenderViewHost* /* render_view_host */) {
+  if (is_main_frame)
+    DetermineIfPageSupportsInstant();
+}
+
 void SearchTabHelper::UpdateMode() {
   SearchMode::Type type = SearchMode::MODE_DEFAULT;
   SearchMode::Origin origin = SearchMode::ORIGIN_DEFAULT;
   if (IsNTP(web_contents_)) {
     type = SearchMode::MODE_NTP;
     origin = SearchMode::ORIGIN_NTP;
   } else if (IsSearchResults(web_contents_)) {
     type = SearchMode::MODE_SEARCH_RESULTS;
     origin = SearchMode::ORIGIN_SEARCH;
   }
   if (user_input_in_progress_)
     type = SearchMode::MODE_SEARCH_SUGGESTIONS;
 
   if (type == SearchMode::MODE_NTP && origin == SearchMode::ORIGIN_NTP &&
       !popup_is_open_ && !user_text_is_empty_) {
     // We're switching back (|popup_is_open_| is false) to an NTP (type and
     // mode are |NTP|) with suggestions (|user_text_is_empty_| is false), don't
     // modify visibility of top bars.  This specific omnibox state is set when
     // OmniboxEditModelChanged() is called from
     // OmniboxEditModel::SetInputInProgress() which is called from
     // OmniboxEditModel::Revert().
     model_.SetState(SearchModel::State(SearchMode(type, origin),
-                                       model_.state().top_bars_visible));
+                                       model_.state().top_bars_visible,
+                                       model_.instant_support()));
   } else {
     model_.SetMode(SearchMode(type, origin));
   }
 }
 
+void SearchTabHelper::DetermineIfPageSupportsInstant() {
+  Profile* profile =
+      Profile::FromBrowserContext(web_contents_->GetBrowserContext());
+  if (!chrome::ShouldAssignURLToInstantRenderer(web_contents_->GetURL(),

[samarth, 2013/05/13 20:19:03]

This seems reasonable but any particular reason you had to add this.

[kmadhusu, 2013/05/14 00:01:27]

During a discussion, Sreeram mentioned about this function and pointed out that
if we know that the URL doesn't belong to an instant renderer, we can
immediately return from this function and avoid dispatching an IPC message to
the renderer.

[sreeram, 2013/05/14 01:49:17]

The idea is that if you send a message to a page that's NOT in the Instant
process, it will never receive it, and will never respond. (In my proposal to
@kmadhusu, the process I recommended was: No need for a tri-state. Keep the
current supports_instant_ state until the response comes back.)

PS: I have yet to review the CL. So I don't know if in fact my proposal is being
implemented (in which case, you do need to perform this check; since otherwise
supports_instant_ will never be updated).

I'll take a look once Samarth is done reviewing.

[samarth, 2013/05/15 17:43:21]

Ok, this check makes sense.

Sreeram: the reason I recommended using a tri-state was so that if you switch to
a tab that we already know to not support instant, we can sever InstantTab
without having to make another IPC.

+                                                profile)) {
+    InstantSupportChanged(false);
+  } else if (IsLocal(web_contents_)) {
+    // Local pages always support Instant.
+    InstantSupportChanged(true);
+  } else {
+    Send(new ChromeViewMsg_DetermineIfPageSupportsInstant(routing_id()));
+  }
+}
+
+void SearchTabHelper::OnInstantSupportDetermined(int page_id,
+                                                 bool supports_instant) {
+  if (web_contents()->IsActiveEntry(page_id))
+    InstantSupportChanged(supports_instant);
+}
+
 void SearchTabHelper::OnSearchBoxShowBars(int page_id) {
   if (web_contents()->IsActiveEntry(page_id))
     model_.SetTopBarsVisible(true);
 }
 
 void SearchTabHelper::OnSearchBoxHideBars(int page_id) {
   if (web_contents()->IsActiveEntry(page_id)) {
     model_.SetTopBarsVisible(false);
     Send(new ChromeViewMsg_SearchBoxBarsHidden(routing_id()));
   }
 }