[AppList] Add a Suggestions Provider to applist.

ui/app_list/search_result.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 UI_APP_LIST_SEARCH_RESULT_H_
 #define UI_APP_LIST_SEARCH_RESULT_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 14 matching lines @@
 
 // SearchResult consists of an icon, title text and details text. Title and
 // details text can have tagged ranges that are displayed differently from
 // default style.
 class APP_LIST_EXPORT SearchResult {
  public:
   // How the result should be displayed.
   enum DisplayType {
     DISPLAY_LIST,
     DISPLAY_TILE,
+    DISPLAY_NONE,
   };
 
   // A tagged range in search result text.
   struct APP_LIST_EXPORT Tag {
     // Similar to ACMatchClassification::Style, the style values are not
     // mutually exclusive.
     enum Style {
       NONE  = 0,
       URL   = 1 << 0,
       MATCH = 1 << 1,
@@ skipping 115 matching lines @@
   int percent_downloaded_;
 
   ObserverList<SearchResultObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(SearchResult);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_SEARCH_RESULT_H_