Chrome suggestions are no longer served if the user doesn't sync his history on a given machine

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/sync/profile_sync_service.h"
+#include "chrome/browser/sync/profile_sync_service_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/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"
@@ skipping 83 matching lines @@
   CoreTabHelper* core_tab_helper = CoreTabHelper::FromWebContents(contents);
   if (core_tab_helper->new_tab_start_time().is_null())
     return;
 
   base::TimeDelta duration =
       base::TimeTicks::Now() - core_tab_helper->new_tab_start_time();
   UMA_HISTOGRAM_TIMES("Tab.NewTabOnload", duration);
   core_tab_helper->set_new_tab_start_time(base::TimeTicks());
 }
 
+// Returns true if the user is signed in and full history sync is enabled,
+// and false otherwise.
+bool IsHistorySyncEnabled(Profile* profile) {
+  ProfileSyncService* sync =
+      ProfileSyncServiceFactory::GetInstance()->GetForProfile(profile);
+  return sync &&
+      sync->sync_initialized() &&
+      sync->GetActiveDataTypes().Has(syncer::HISTORY_DELETE_DIRECTIVES);

[Jered, 2014/06/17 22:38:19]

I don't understand what HISTORY_DELETE_DIRECTIVES is or does, but I'll trust
that this is what you need.

[beaudoin, 2014/06/18 13:49:04]

It's the one used by other pieces of the code that look at that checkbox state.
I verified it works. Maybe SESSIONS would work too, but I'd rather go with the
one everybody else is using.

+}
+
 }  // namespace
 
 SearchTabHelper::SearchTabHelper(content::WebContents* web_contents)
     : WebContentsObserver(web_contents),
       is_search_enabled_(chrome::IsInstantExtendedAPIEnabled()),
       web_contents_(web_contents),
       ipc_router_(web_contents, this,
                   make_scoped_ptr(new SearchIPCRouterPolicyImpl(web_contents))
                       .PassAs<SearchIPCRouter::Policy>()),
       instant_service_(NULL),
@@ skipping 386 matching lines @@
   omnibox->SetUserText(text_to_paste);
   omnibox->OnAfterPossibleChange();
 #endif
 }
 
 void SearchTabHelper::OnChromeIdentityCheck(const base::string16& identity) {
   SigninManagerBase* manager = SigninManagerFactory::GetForProfile(profile());
   if (manager) {
     const base::string16 username =
         base::UTF8ToUTF16(manager->GetAuthenticatedUsername());
-    ipc_router_.SendChromeIdentityCheckResult(identity,
-                                              identity == username);
+    // The identity check only passes if the user is syncing their history.
+    // TODO(beaudoin): Change this function name and related APIs now that it's
+    // checking both the identity and the user's sync state.
+    bool matches = IsHistorySyncEnabled(profile()) && identity == username;
+    ipc_router_.SendChromeIdentityCheckResult(identity, matches);
   }
 }
 
 void SearchTabHelper::UpdateMode(bool update_origin, bool is_preloaded_ntp) {
   SearchMode::Type type = SearchMode::MODE_DEFAULT;
   SearchMode::Origin origin = SearchMode::ORIGIN_DEFAULT;
   if (IsNTP(web_contents_) || is_preloaded_ntp) {
     type = SearchMode::MODE_NTP;
     origin = SearchMode::ORIGIN_NTP;
   } else if (IsSearchResults(web_contents_)) {
@@ skipping 46 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;
 }