Don't autocomplete searches of >1 word if they've only been visited once and the user has not yet...

chrome/browser/autocomplete/autocomplete.h

 // Copyright (c) 2011 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 472 matching lines @@
     // |destination_url|, we'll use the best match from this provider.
     const AutocompleteProvider* provider_affinity;
 
     // True when this is the HistoryURLProvider's "what you typed" match.  This
     // can't be tracked using |destination_url| because its URL changes on every
     // keystroke, so if this is set, we'll preserve the selection by simply
     // choosing the new "what you typed" entry and ignoring |destination_url|.
     bool is_history_what_you_typed_match;
   };
 
+  // Max number of matches we'll show from the various providers.
+  static const size_t kMaxMatches;
+
+  // The lowest score a match can have and still potentially become the default
+  // match for the result set.
+  static const int kLowestDefaultScore;
+
   AutocompleteResult();
   ~AutocompleteResult();
 
   // operator=() by another name.
   void CopyFrom(const AutocompleteResult& rhs);
 
   // Copies matches from |old_matches| to provide a consistant result set. See
   // comments in code for specifics.
   void CopyOldMatches(const AutocompleteInput& input,
                       const AutocompleteResult& old_matches);
@@ skipping 34 matching lines @@
   // Clears the matches for this result set.
   void Reset();
 
   void Swap(AutocompleteResult* other);
 
 #ifndef NDEBUG
   // Does a data integrity check on this result.
   void Validate() const;
 #endif
 
-  // Max number of matches we'll show from the various providers.
-  static const size_t kMaxMatches;
-
  private:
   typedef std::map<AutocompleteProvider*, ACMatches> ProviderToMatches;
 
   // Populates |provider_to_matches| from |matches_|.
   void BuildProviderToMatches(ProviderToMatches* provider_to_matches) const;
 
   // Returns true if |matches| contains a match with the same destination as
   // |match|.
   static bool HasMatchByDestination(const AutocompleteMatch& match,
                                     const ACMatches& matches);
@@ skipping 189 matching lines @@
   AutocompleteInput::Type input_type;
   // Selected index (if selected) or -1 (AutocompletePopupModel::kNoMatch).
   size_t selected_index;
   // Inline autocompleted length (if displayed).
   size_t inline_autocompleted_length;
   // Result set.
   const AutocompleteResult& result;
 };
 
 #endif  // CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_H_