autocomplete: Make ContactProvider rank contacts by affinity

chrome/browser/autocomplete/contact_provider_chromeos.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_CONTACT_PROVIDER_CHROMEOS_H_
 #define CHROME_BROWSER_AUTOCOMPLETE_CONTACT_PROVIDER_CHROMEOS_H_
 
 #include <utility>
 #include <vector>
 
@@ skipping 12 matching lines @@
 
 // AutocompleteProvider implementation that searches through the contacts
 // provided by contacts::ContactManager.
 class ContactProvider : public AutocompleteProvider,
                         public contacts::ContactManagerObserver {
  public:
   // Key within AutocompleteMatch::additional_info where the corresponding
   // contact's ID is stored.
   static const char kMatchContactIdKey[];
 
+  // Base match relevance assigned to a contact with an affinity of 0.0.
+  static const int kBaseRelevance;
+
+  // Maximum boost to relevance for a contact with an affinity of 1.0.
+  static const int kAffinityRelevanceBoost;
+
   ContactProvider(
       AutocompleteProviderListener* listener,
       Profile* profile,
       base::WeakPtr<contacts::ContactManagerInterface> contact_manager);
 
   // AutocompleteProvider overrides:
   virtual void Start(const AutocompleteInput& input,
                      bool minimal_changes) OVERRIDE;
 
   // contacts::ContactManagerObserver overrides:
@@ skipping 15 matching lines @@
   void AddContactIfMatched(const AutocompleteInput& input,
                            const std::vector<string16>& input_words,
                            const ContactData& contact);
 
   // Returns an AutocompleteMatch object corresponding to the passed-in data.
   AutocompleteMatch CreateAutocompleteMatch(const AutocompleteInput& input,
                                             const ContactData& contact);
 
   base::WeakPtr<contacts::ContactManagerInterface> contact_manager_;
 
-  // Contacts through which we search.
+  // Contacts through which we search, ordered by descending affinity.
   ContactDataVector contacts_;
 
   DISALLOW_COPY_AND_ASSIGN(ContactProvider);
 };
 
 #endif  // CHROME_BROWSER_AUTOCOMPLETE_CONTACT_PROVIDER_CHROMEOS_H_