Show the message 'No files match "abc"' if the search results are empty.

chrome/browser/resources/file_manager/js/file_manager.js

 // 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.
 
 /**
  * FileManager constructor.
  *
  * FileManager objects encapsulate the functionality of the file selector
  * dialogs, as well as the full screen file manager application (though the
  * latter is not yet implemented).
@@ skipping 4353 matching lines @@
       event.target.setAttribute('checked', 'checked');
     else
       event.target.removeAttribute('checked');
 
     var changeInfo = {};
     changeInfo[pref] = inverted ? !newValue : newValue;
     chrome.fileBrowserPrivate.setGDataPreferences(changeInfo);
   };
 
   FileManager.prototype.onSearchBoxUpdate_ = function(event) {
-    var searchString = this.dialogDom_.querySelector('#search-box').value;
+    var searchString = this.document_.getElementById('search-box').value;
+    var searchStringLC = searchString.toLowerCase();
+    var noResultsDiv = this.document_.getElementById('no-search-results');
     if (searchString) {
       this.directoryModel_.addFilter(
           'searchbox',
           function(e) {
-            return e.name.substr(0, searchString.length) == searchString;
+            return e.name.toLowerCase().indexOf(searchStringLC) > -1;
           });
+
+      this.reportEmptySearchResults_ = function() {
+        if (this.directoryModel_.getFileList().length === 0) {
+          var text = strf('SEARCH_NO_MATCHING_FILES', searchString);
+          noResultsDiv.innerHTML = text;
+          noResultsDiv.hidden = false;
+        }
+      }.bind(this);
+
+      this.directoryModel_.addEventListener(
+          'rescan-completed', this.reportEmptySearchResults_);
     } else {
       this.directoryModel_.removeFilter('searchbox');
+      noResultsDiv.hidden = true;
+      this.directoryModel_.removeEventListener(
+          'rescan-completed', this.reportEmptySearchResults_);
     }
   };
 
   FileManager.prototype.decorateSplitter = function(splitterElement) {
     var self = this;
 
     var Splitter = cr.ui.Splitter;
 
     var customSplitter = cr.ui.define('div');
 
@@ skipping 142 matching lines @@
 
     function closeBanner() {
       self.cleanupGDataWelcome_();
       // Stop showing the welcome banner.
       localStorage[WELCOME_HEADER_COUNTER_KEY] = WELCOME_HEADER_COUNTER_LIMIT;
     }
 
     return maybeShowBanner;
   };
 })();