Add support for providers called when the omnibox is focused.

chrome/browser/autocomplete/autocomplete_controller.h

 // Copyright (c) 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.
 
 #ifndef CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_CONTROLLER_H_
 #define CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_CONTROLLER_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
@@ skipping 62 matching lines @@
   // sent.
   void Start(const AutocompleteInput& input);
 
   // Cancels the current query, ensuring there will be no future notifications
   // fired.  If new matches have come in since the most recent notification was
   // fired, they will be discarded.
   //
   // If |clear_result| is true, the controller will also erase the result set.
   void Stop(bool clear_result);
 
-  // Begin asynchronous fetch of zero-suggest suggestions. The |input| should
-  // contain current omnibox input, the URL of the page we are on, and
-  // that page's classification.
-  void StartZeroSuggest(const AutocompleteInput& input);
+  // Begin asynchronous fetch of suggestions to be shown when the omnibox is
+  // focused. The |input| should contain current omnibox input, the URL of the
+  // page we are on, and that page's classification.
+  void StartOnOmniboxFocus(const AutocompleteInput& input);

[Peter Kasting, 2014/12/30 21:18:23]

Nit: How about this comment and name:

  // Called when the omnibox is focused while no existing user input is in
  // progress.  This is used to trigger any providers which want to provide
  // matches in response to focus.  See
  // AutocompleteProvider::ProvidesMatchesOnOmniboxFocus().
  void OnOmniboxFocused(const AutocompleteInput& input);

[jif, 2014/12/31 19:02:26]

Done.

 
   // Asks the relevant provider to delete |match|, and ensures observers are
   // notified of resulting changes immediately.  This should only be called when
   // no query is running.
   void DeleteMatch(const AutocompleteMatch& match);
 
   // Removes any entries that were copied from the last result. This is used by
   // the popup to ensure it's not showing an out-of-date query.
   void ExpireCopiedEntries();
 
@@ skipping 107 matching lines @@
   Providers providers_;
 
   HistoryURLProvider* history_url_provider_;
 
   KeywordProvider* keyword_provider_;
 
   SearchProvider* search_provider_;
 
   ZeroSuggestProvider* zero_suggest_provider_;
 
+  // Returns whether |providers_| contains providers that are started when the
+  // omnibox is focused.
+  bool has_providers_for_omnibox_focus_;
+
   // Input passed to Start.
   AutocompleteInput input_;
 
   // Data from the autocomplete query.
   AutocompleteResult result_;
 
   // The most recent time the default match (inline match) changed.  This may
   // be earlier than the most recent keystroke if the recent keystrokes didn't
   // change the suggested match in the omnibox.  (For instance, if
   // a user typed "mail.goog" and the match https://mail.google.com/ was
@@ skipping 25 matching lines @@
   // Are we in Start()? This is used to avoid updating |result_| and sending
   // notifications until Start() has been invoked on all providers.
   bool in_start_;
 
   TemplateURLService* template_url_service_;
 
   DISALLOW_COPY_AND_ASSIGN(AutocompleteController);
 };
 
 #endif  // CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_CONTROLLER_H_