Omnibox: Add Mid-Input Matching to HistoryQuick Provider

chrome/browser/autocomplete/history_quick_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/history_quick_provider.h"
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
@@ skipping 145 matching lines @@
   DCHECK(match.destination_url.is_valid());
   // Delete the match from the InMemoryURLIndex.
   GetIndex()->DeleteURL(match.destination_url);
   DeleteMatchFromMatches(match);
 }
 
 HistoryQuickProvider::~HistoryQuickProvider() {}
 
 void HistoryQuickProvider::DoAutocomplete() {
   // Get the matching URLs from the DB.
-  string16 term_string = autocomplete_input_.text();
-  ScoredHistoryMatches matches = GetIndex()->HistoryItemsForTerms(term_string);
+  ScoredHistoryMatches matches = GetIndex()->HistoryItemsForTerms(
+      autocomplete_input_.text(),
+      autocomplete_input_.cursor_position());

[sky, 2013/02/06 04:59:43]

If the cursor position factors into the results does this mean the query needs
to be rerun when the cursor position changes?

[Mark P, 2013/02/06 17:53:34]

Kind of, yes.  But we decided that in order to avoid disruptive visual changes,
we'd only resend the omnibox query when the input text changes.  This means if
the user puts the cursor in the middle and deletes a character or types a new
character, we'd send a new query, but simply pressing left arrow to get the
middle will not go through tons of changing autocomplete suggestions.  This is
already how the omnibox edit model works, so this changelist needs no additional
changes for that.

   if (matches.empty())
     return;
 
   // If we're allowed to reorder results in order to get an inlineable
   // result to appear first (and hence have a HistoryQuickProvider
   // suggestion possibly appear first), find the first inlineable
   // result and then swap it to the front.  Obviously, don't do this
   // if we're told to prevent inline autocompletion.  (If we're told
   // we're going to prevent inline autocompletion, we're going to
   // later demote the score of all results so none will be inlined.
@@ skipping 218 matching lines @@
     do {
       offset += matches[i].length;
       ++i;
     } while ((i < match_count) && (offset == matches[i].offset));
     if (offset < text_length)
       spans.push_back(ACMatchClassification(offset, url_style));
   }
 
   return spans;
 }