[Autofill] Fill fields that have an autocomplete attributes even if not in a form.

components/autofill/core/browser/form_structure_unittest.cc

Index: components/autofill/core/browser/form_structure_unittest.cc
diff --git a/components/autofill/core/browser/form_structure_unittest.cc b/components/autofill/core/browser/form_structure_unittest.cc
index 4d1812a3e88f58796042e7029f7c07fbefb2335c..21e9945456f52488d9573626f8f347ff8d9802df 100644
--- a/components/autofill/core/browser/form_structure_unittest.cc
+++ b/components/autofill/core/browser/form_structure_unittest.cc
@@ -451,6 +451,58 @@ TEST_F(FormStructureTest, HeuristicsAutocompleteAttribute) {
   EXPECT_EQ(UNKNOWN_TYPE, form_structure->field(2)->heuristic_type());
 }
 
+// Verify that the heuristics are not run for non checkout formless forms.
+TEST_F(FormStructureTest, Heuristics_FormlessNonCheckoutForm) {
+  scoped_ptr<FormStructure> form_structure;
+  FormData form;
+
+  FormFieldData field;
+  field.form_control_type = "text";
+
+  field.label = ASCIIToUTF16("First Name:");
+  field.name = ASCIIToUTF16("firstname");
+  field.autocomplete_attribute = "given-name";
+  form.fields.push_back(field);
+
+  field.label = ASCIIToUTF16("Last Name:");
+  field.name = ASCIIToUTF16("lastname");
+  field.autocomplete_attribute = "family-name";
+  form.fields.push_back(field);
+
+  field.label = ASCIIToUTF16("Email:");
+  field.name = ASCIIToUTF16("email");
+  field.autocomplete_attribute = "email";
+  form.fields.push_back(field);
+
+  form_structure.reset(new FormStructure(form));
+  form_structure->DetermineHeuristicTypes();
+  EXPECT_TRUE(form_structure->IsAutofillable());
+
+  // Expect the correct number of fields.
+  ASSERT_EQ(3U, form_structure->field_count());
+  ASSERT_EQ(3U, form_structure->autofill_count());
+
+  // The heuristic type should be good.
+  EXPECT_EQ(HTML_TYPE_GIVEN_NAME, form_structure->field(0)->html_type());
+  EXPECT_EQ(NAME_FIRST, form_structure->field(0)->heuristic_type());
+
+  // Set the form as a formless non checkout form.
+  form.is_formless_checkout = false;
+  form.is_form_tag = false;
+
+  form_structure.reset(new FormStructure(form));
+  form_structure->DetermineHeuristicTypes();
+  EXPECT_TRUE(form_structure->IsAutofillable());
+
+  // Expect the correct number of fields.
+  ASSERT_EQ(3U, form_structure->field_count());
+  ASSERT_EQ(3U, form_structure->autofill_count());
+
+  // The heuristic type should be Unknown.
+  EXPECT_EQ(HTML_TYPE_GIVEN_NAME, form_structure->field(0)->html_type());
+  EXPECT_EQ(UNKNOWN_TYPE, form_structure->field(0)->heuristic_type());
+}
+
 // All fields share a common prefix which could confuse the heuristics. Test
 // that the common prefix is stripped out before running heuristics.
 TEST_F(FormStructureTest, StripCommonNamePrefix) {