Omnibox: Make the Controller Reorder Matches for Inlining

chrome/browser/autocomplete/shortcuts_provider.cc

 // 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.
 
 #include "chrome/browser/autocomplete/shortcuts_provider.h"
 
 #include <algorithm>
 #include <cmath>
 #include <map>
 #include <vector>
@@ skipping 157 matching lines @@
       matches_.push_back(ShortcutToACMatch(relevance, term_string, it->second));
   }
   std::partial_sort(matches_.begin(),
       matches_.begin() +
           std::min(AutocompleteProvider::kMaxMatches, matches_.size()),
       matches_.end(), &AutocompleteMatch::MoreRelevant);
   if (matches_.size() > AutocompleteProvider::kMaxMatches) {
     matches_.erase(matches_.begin() + AutocompleteProvider::kMaxMatches,
                    matches_.end());
   }
-  // Reset relevance scores to guarantee no results are given an
-  // inlineable score and all scores are decreasing (but not do assign
-  // any scores below 1).
-  max_relevance = AutocompleteResult::kLowestDefaultScore - 1;
-  for (ACMatches::iterator it = matches_.begin(); it != matches_.end(); ++it) {
-    max_relevance = std::min(max_relevance, it->relevance);
-    it->relevance = max_relevance;
-    if (max_relevance > 1)
-      --max_relevance;
+  // Reset relevance scores to guarantee no match is given a score that may
+  // allow it to become the highest ranked match (i.e., the default match)
+  // unless the omnibox will reorder matches as necessary to correct the
+  // problem.  (Shortcuts matches are sometimes not inline-autocompletable
+  // and, even when they are, the ShortcutsProvider does not bother to set
+  // |inline_autocompletion|.  Hence these matches can never be displayed
+  // corectly in the omnibox as the default match.)  In the process of
+  // resetting scores, guarantee that all scores are decreasing (but do
+  // not assign any scores below 1).
+  if (!OmniboxFieldTrial::ReorderForLegalDefaultMatch(
+      input.current_page_classification())) {
+    int max_relevance = AutocompleteResult::kLowestDefaultScore - 1;
+    for (ACMatches::iterator it = matches_.begin(); it != matches_.end();
+        ++it) {
+      max_relevance = std::min(max_relevance, it->relevance);
+      it->relevance = max_relevance;
+      if (max_relevance > 1)
+        --max_relevance;
+    }
   }
 }
 
 AutocompleteMatch ShortcutsProvider::ShortcutToACMatch(
     int relevance,
     const string16& term_string,
     const history::ShortcutsBackend::Shortcut& shortcut) {
   DCHECK(!term_string.empty());
   AutocompleteMatch match(this, relevance, true,
                           AutocompleteMatchType::HISTORY_TITLE);
@@ skipping 169 matching lines @@
   // (1.0 / each 5 additional hits), up to a maximum of 5x as long.
   const double kMaxDecaySpeedDivisor = 5.0;
   const double kNumUsesPerDecaySpeedDivisorIncrement = 5.0;
   double decay_divisor = std::min(kMaxDecaySpeedDivisor,
       (shortcut.number_of_hits + kNumUsesPerDecaySpeedDivisorIncrement - 1) /
       kNumUsesPerDecaySpeedDivisorIncrement);
 
   return static_cast<int>((base_score / exp(decay_exponent / decay_divisor)) +
       0.5);
 }