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

chrome/browser/ui/search/search_ipc_router.h

 // Copyright 2013 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.
 
 #ifndef CHROME_BROWSER_UI_SEARCH_SEARCH_IPC_ROUTER_H_
 #define CHROME_BROWSER_UI_SEARCH_SEARCH_IPC_ROUTER_H_
 
 #include <vector>
 
 #include "base/gtest_prod_util.h"
@@ skipping 59 matching lines @@
     virtual void OnLogMostVisitedNavigation(int position,
                                             const base::string16& provider) = 0;
 
     // Called when the page wants to paste the |text| (or the clipboard contents
     // if the |text| is empty) into the omnibox.
     virtual void PasteIntoOmnibox(const base::string16& text) = 0;
 
     // Called when the SearchBox wants to verify the signed-in Chrome identity
     // against the provided |identity|. Will make a round-trip to the browser
     // and eventually return the result through SendChromeIdentityCheckResult.
+    // Calls SendChromeIdentityCheckResult with true if both the identity
+    // matches and the user syncs 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.
     virtual void OnChromeIdentityCheck(const base::string16& identity) = 0;
   };
 
   // An interface to be implemented by consumers of SearchIPCRouter objects to
   // decide whether to process the message received from the page, and vice
   // versa (decide whether to send messages to the page).
   class Policy {
    public:
     virtual ~Policy() {}
 
@@ skipping 134 matching lines @@
   // SearchIPCRouter to ensure that delayed IPC replies are ignored.
   int commit_counter_;
 
   // Set to true, when the tab corresponding to |this| instance is active.
   bool is_active_tab_;
 
   DISALLOW_COPY_AND_ASSIGN(SearchIPCRouter);
 };
 
 #endif  // CHROME_BROWSER_UI_SEARCH_SEARCH_IPC_ROUTER_H_