Omnibox: Don't Barf When Suggestion is Mixed-Case Equivalent to Verbatim

components/omnibox/browser/base_search_provider.cc

 // Copyright 2014 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 "components/omnibox/browser/base_search_provider.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/i18n/case_conversion.h"
@@ skipping 214 matching lines @@
         static_cast<int>(
             suggestion.suggestion().length() - match.contents.length()));
   }
 
   if (!suggestion.annotation().empty()) {
     match.description = suggestion.annotation();
     AutocompleteMatch::AddLastClassificationIfNecessary(
         &match.description_class, 0, ACMatchClassification::NONE);
   }
 
+  const base::string16 input_lower = base::i18n::ToLower(input.text());
   // suggestion.match_contents() should have already been collapsed.
   match.allowed_to_be_default_match =
       (!in_keyword_mode || suggestion.from_keyword_provider()) &&
-      (base::CollapseWhitespace(input.text(), false) ==
-       suggestion.match_contents());
+      (base::CollapseWhitespace(input_lower, false) ==
+       base::i18n::ToLower(suggestion.match_contents()));
 
   // When the user forced a query, we need to make sure all the fill_into_edit
   // values preserve that property.  Otherwise, if the user starts editing a
   // suggestion, non-Search results will suddenly appear.
   if (input.type() == metrics::OmniboxInputType::FORCED_QUERY)
     match.fill_into_edit.assign(base::ASCIIToUTF16("?"));
   if (suggestion.from_keyword_provider())
     match.fill_into_edit.append(match.keyword + base::char16(' '));
   // We only allow inlinable navsuggestions that were received before the
   // last keystroke because we don't want asynchronous inline autocompletions.
   if (!input.prevent_inline_autocomplete() &&
       !suggestion.received_after_last_keystroke() &&
       (!in_keyword_mode || suggestion.from_keyword_provider()) &&
       base::StartsWith(
-          base::i18n::ToLower(suggestion.suggestion()),
-          base::i18n::ToLower(input.text()), base::CompareCase::SENSITIVE)) {
+          base::i18n::ToLower(suggestion.suggestion()), input_lower,
+          base::CompareCase::SENSITIVE)) {
     match.inline_autocompletion =
         suggestion.suggestion().substr(input.text().length());
     match.allowed_to_be_default_match = true;
   }
   match.fill_into_edit.append(suggestion.suggestion());
 
   const TemplateURLRef& search_url = template_url->url_ref();
   DCHECK(search_url.SupportsReplacement(search_terms_data));
   match.search_terms_args.reset(
       new TemplateURLRef::SearchTermsArgs(suggestion.suggestion()));
@@ skipping 215 matching lines @@
 
 void BaseSearchProvider::OnDeletionComplete(
     bool success, SuggestionDeletionHandler* handler) {
   RecordDeletionResult(success);
   deletion_handlers_.erase(std::remove_if(
       deletion_handlers_.begin(), deletion_handlers_.end(),
       [handler](const scoped_ptr<SuggestionDeletionHandler>& elem) {
           return elem.get() == handler;
       }));
 }