Add a term feature extractor for client-side phishing detection.

chrome/renderer/safe_browsing/features.h

 // Copyright (c) 2010 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.
 //
 // Common types and constants for extracting and evaluating features in the
 // client-side phishing detection model.  A feature is simply a string and an
 // associated floating-point value between 0 and 1.  The phishing
 // classification model contains rules which give an appropriate weight to each
 // feature or combination of features.  These values can then be summed to
 // compute a final phishiness score.
@@ skipping 140 matching lines @@
 // Set if the number of <script> elements in the page is greater than 6.
 extern const char kPageNumScriptTagsGTSix[];
 
 ////////////////////////////////////////////////////
 // Other DOM HTML features
 ////////////////////////////////////////////////////
 
 // The fraction of images whose src attribute points to an external domain.
 extern const char kPageImgOtherDomainFreq[];
 
+////////////////////////////////////////////////////
+// Page term features
+////////////////////////////////////////////////////
+
+// Token feature for a term (whitespace-delimited) on a page.  Terms can be
+// single words or multi-word n-grams.  Rather than adding this feature for
+// every possible token on a page, only the terms that are mentioned in the
+// classification model are added.
+extern const char kPageTerm[];
+
 }  // namespace features
 }  // namepsace safe_browsing
 
 #endif  // CHROME_RENDERER_SAFE_BROWSING_FEATURES_H_