Omnibox SearchProvider Experiment Client Implementation.

chrome/browser/autocomplete/autocomplete.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_H_
 #define CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 155 matching lines @@
 // HistoryContents (any match in body of nonstarred page)              |  500++
 //
 // (A search keyword is a keyword with a replacement string; a bookmark keyword
 // is a keyword with no replacement string, that is, a shortcut for a URL.)
 //
 // There are two possible providers for search suggestions. If the user has
 // typed a keyword, then the primary provider is the keyword provider and the
 // secondary provider is the default provider. If the user has not typed a
 // keyword, then the primary provider corresponds to the default provider.
 //
+// Search providers may supply relevance values along with their results to be
+// used in place of client-side calculated values. See http://crbug.com/125871

[Peter Kasting, 2012/06/05 00:47:51]

Nit: I'd just omit the bug reference

[msw, 2012/06/05 01:49:41]

Done.

+//
 // The value column gives the ranking returned from the various providers.
 // ++: a series of matches with relevance from n up to (n + max_matches).
 // --: relevance score falls off over time (discounted 50 points @ 15 minutes,
 //     450 points @ two weeks)
 // **: relevance score falls off over two days (discounted 99 points after two
 //     days).
 // *~: Partial matches get a score on a sliding scale from about 575-1125 based
 //     on how many times the URL for the Extension App has been typed and how
 //     many of the letters match.
 
@@ skipping 644 matching lines @@
   size_t inline_autocompleted_length;
   // Result set.
   const AutocompleteResult& result;
   // Diagnostic information from providers.  See
   // AutocompleteController::AddProvidersInfo() and
   // AutocompleteProvider::AddProviderInfo() above.
   ProvidersInfo providers_info;
 };
 
 #endif  // CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_H_