autocomplete: Make ContactProvider rank contacts by affinity

chrome/browser/autocomplete/contact_provider_chromeos.h

Index: chrome/browser/autocomplete/contact_provider_chromeos.h
diff --git a/chrome/browser/autocomplete/contact_provider_chromeos.h b/chrome/browser/autocomplete/contact_provider_chromeos.h
index 9880aa0bb42274c30e73b36096858b64419ec9b4..ca873ad87da87d9e32688a8c35565f6ca4cd5ac0 100644
--- a/chrome/browser/autocomplete/contact_provider_chromeos.h
+++ b/chrome/browser/autocomplete/contact_provider_chromeos.h
@@ -30,6 +30,12 @@ class ContactProvider : public AutocompleteProvider,
   // 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,
@@ -65,7 +71,7 @@ class ContactProvider : public AutocompleteProvider,
 
   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);