Prevent autofilling credit card security number fields with passwords.

components/autofill/content/renderer/password_form_conversion_utils_browsertest.cc

 // Copyright 2013 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 <stddef.h>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_util.h"
@@ skipping 1273 matching lines @@
   std::string html = builder.ProduceHTML();
 
   std::map<int, PasswordFormFieldPredictionType> predictions_positions;
   predictions_positions[2] = PREDICTION_NOT_PASSWORD;
 
   FormsPredictionsMap predictions;
   SetPredictions(html, &predictions, predictions_positions);
 
   std::unique_ptr<PasswordForm> password_form =
       LoadHTMLAndConvertForm(html, &predictions, false);
-  EXPECT_TRUE(password_form);
+  EXPECT_FALSE(password_form);
 }
 
 TEST_F(MAYBE_PasswordFormConversionUtilsTest, IsGaiaReauthFormIgnored) {
   struct TestCase {
     const char* origin;
     struct KeyValue {
       KeyValue() : name(nullptr), value(nullptr) {}
       KeyValue(const char* new_name, const char* new_value)
           : name(new_name), value(new_value) {}
       const char* name;
@@ skipping 265 matching lines @@
 
   ASSERT_TRUE(password_form);
 
   EXPECT_EQ(base::UTF8ToUTF16("username"), password_form->username_element);
   EXPECT_EQ(base::UTF8ToUTF16("johnsmith"), password_form->username_value);
   EXPECT_EQ(base::UTF8ToUTF16("password"), password_form->password_element);
   EXPECT_EQ(base::UTF8ToUTF16("secret"), password_form->password_value);
 }
 
 }  // namespace autofill