Track confidence calculations better. Reduce minimum user text length.

chrome/browser/autocomplete/network_action_predictor.h

Index: chrome/browser/autocomplete/network_action_predictor.h
diff --git a/chrome/browser/autocomplete/network_action_predictor.h b/chrome/browser/autocomplete/network_action_predictor.h
index 20b570815752a92fe6ceffdeb6d59db08cb3a124..35f49154c0cf7d9e64153dc4f322cc610a0a272e 100644
--- a/chrome/browser/autocomplete/network_action_predictor.h
+++ b/chrome/browser/autocomplete/network_action_predictor.h
@@ -141,9 +141,11 @@ class NetworkActionPredictor
   bool TryDeleteOldEntries(HistoryService* service);
 
   // Uses local caches to calculate an exact percentage prediction that the user
-  // will take a particular match given what they have typed.
-  double ExactAlgorithm(const string16& user_text,
-                        const AutocompleteMatch& match) const;
+  // will take a particular match given what they have typed. |is_in_db| is set
+  // to differentiate trivial zero results from actual zero results.

[Peter Kasting, 2011/12/08 00:10:24]

Nit: You might want to give more detail here on what these terms mean.

+  double CalculateConfidence(const string16& user_text,
+                             const AutocompleteMatch& match,
+                             bool* is_in_db) const;
 
   // Adds a row to the database and caches.
   void AddRow(const DBCacheKey& key,