[Password Manager] Add parser annotations to HTML <form> if

#enable-show-autofill-signatures flag is enabled.

<form name="change_password_form" >
  <input type="text" name="username" pm_parser_annotation="username_element" >
  <input type="password" name="current-password" pm_parser_annotation="password_element" >
  <input type="password" name="new-password" pm_parser_annotation="new_password_element" >
  <input type="password" name="password-again" pm_parser_annotation="confirmation_password_element" >
</form>

Bug: 824793
Change-Id: Ie02de13798abfc0aca0dfe9c47667ff4c52b4163
Reviewed-on: https://chromium-review.googlesource.com/1151315
Commit-Queue: Maxim Kolosovskiy <kolos@chromium.org>
Reviewed-by: Dominic Battré <battre@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579335}

chrome/renderer/autofill/password_autofill_agent_browsertest.cc

@@ -3284,8 +3284,7 @@ TEST_F(PasswordAutofillAgentTest, ShowAutofillSignaturesFlag) {
 
     // Check only form signature attribute. The full test is in
     // "PasswordGenerationAgentTestForHtmlAnnotation.*".
-    WebString form_signature_attribute =
-        WebString::FromASCII(kDebugAttributeForFormSignature);
+    WebString form_signature_attribute = WebString::FromASCII("form_signature");
     EXPECT_EQ(form_element.HasAttribute(form_signature_attribute),
               show_signatures);
   }

chrome/renderer/autofill/password_generation_agent_browsertest.cc

@@ -1001,6 +1001,11 @@ TEST_F(PasswordGenerationAgentTestForHtmlAnnotation, AnnotateForm) {
     blink::WebString form_signature_in_username = username_element.GetAttribute(
         blink::WebString::FromUTF8("form_signature"));
     EXPECT_EQ(kFormSignature, form_signature_in_username.Ascii());
+    EXPECT_EQ(
+        "username_element",
+        username_element
+            .GetAttribute(blink::WebString::FromUTF8("pm_parser_annotation"))
+            .Ascii());
 
     blink::WebElement password_element =
         document.GetElementById(blink::WebString::FromUTF8("first_password"));
@@ -1012,12 +1017,31 @@ TEST_F(PasswordGenerationAgentTestForHtmlAnnotation, AnnotateForm) {
     blink::WebString form_signature_in_password = password_element.GetAttribute(
         blink::WebString::FromUTF8("form_signature"));
     EXPECT_EQ(kFormSignature, form_signature_in_password.Ascii());
+    // The parser annotation is based on local heuristics, but not server side
+    // prediction. So, the new password element is classified as the current
+    // password.
+    EXPECT_EQ(
+        "password_element",
+        password_element
+            .GetAttribute(blink::WebString::FromUTF8("pm_parser_annotation"))
+            .Ascii());
 
     // Check the generation element is marked.
     blink::WebString generation_mark = password_element.GetAttribute(
         blink::WebString::FromUTF8("password_creation_field"));
     ASSERT_FALSE(generation_mark.IsNull());
     EXPECT_EQ("1", generation_mark.Utf8());
+
+    blink::WebElement confirmation_password_element =
+        document.GetElementById(blink::WebString::FromUTF8("second_password"));
+    // The parser annotation is based on local heuristics, but not server side
+    // prediction. So, the confirmation password element is classified as the
+    // new password.
+    EXPECT_EQ(
+        "new_password_element",
+        confirmation_password_element
+            .GetAttribute(blink::WebString::FromUTF8("pm_parser_annotation"))
+            .Ascii());
   }
 }
 

components/autofill/content/renderer/password_autofill_agent.cc

@@ -79,6 +79,11 @@ const size_t kMaximumTextSizeForAutocomplete = 1000;
 const char kDummyUsernameField[] = "anonymous_username";
 const char kDummyPasswordField[] = "anonymous_password";
 
+// Names of HTML attributes to show form and field signatures for debugging.
+const char kDebugAttributeForFormSignature[] = "form_signature";
+const char kDebugAttributeForFieldSignature[] = "field_signature";
+const char kDebugAttributeForParserAnnotations[] = "pm_parser_annotation";
+
 // Maps element names to the actual elements to simplify form filling.
 typedef std::map<base::string16, WebInputElement> FormInputElementMap;
 
@@ -524,11 +529,33 @@ WebString GetFormSignatureAsWebString(const PasswordForm& password_form) {
       base::NumberToString(CalculateFormSignature(password_form.form_data)));
 }
 
+// Add parser annotations saved in |password_form| to |element|.
+void AddParserAnnotations(PasswordForm* password_form,
+                          blink::WebFormControlElement* element) {
+  base::string16 element_name = element->NameForAutofill().Utf16();
+  std::string attribute_value;
+  if (password_form->username_element == element_name) {
+    attribute_value = "username_element";
+  } else if (password_form->password_element == element_name) {
+    attribute_value = "password_element";
+  } else if (password_form->new_password_element == element_name) {
+    attribute_value = "new_password_element";
+  } else if (password_form->confirmation_password_element == element_name) {
+    attribute_value = "confirmation_password_element";
+  }
+  element->SetAttribute(
+      blink::WebString::FromASCII(kDebugAttributeForParserAnnotations),
+      attribute_value.empty() ? blink::WebString()
+                              : blink::WebString::FromASCII(attribute_value));
+}
+
 // Annotate |fields| with field signatures and form signature as HTML
 // attributes.
-void AnnotateFieldsWithSignatures(std::vector<WebFormControlElement>* fields,
-                                  const WebString& form_signature) {
-  for (WebFormControlElement& control_element : *fields) {
+void AnnotateFieldsWithSignatures(
+    std::vector<blink::WebFormControlElement>* fields,
+    const blink::WebString& form_signature,
+    PasswordForm* password_form) {
+  for (blink::WebFormControlElement& control_element : *fields) {
     FieldSignature field_signature = CalculateFieldSignatureByNameAndType(
         control_element.NameForAutofill().Utf16(),
         control_element.FormControlTypeForAutofill().Utf8());
@@ -536,7 +563,10 @@ void AnnotateFieldsWithSignatures(std::vector<WebFormControlElement>* fields,
         WebString::FromASCII(kDebugAttributeForFieldSignature),
         WebString::FromUTF8(base::NumberToString(field_signature)));
     control_element.SetAttribute(
-        WebString::FromASCII(kDebugAttributeForFormSignature), form_signature);
+        blink::WebString::FromASCII(kDebugAttributeForFormSignature),
+        form_signature);
+    if (password_form)
+      AddParserAnnotations(password_form, &control_element);
   }
 }
 
@@ -555,7 +585,8 @@ void AnnotateFormsAndFieldsWithSignatures(WebLocalFrame* frame,
     }
     std::vector<WebFormControlElement> form_fields =
         form_util::ExtractAutofillableElementsInForm(form);
-    AnnotateFieldsWithSignatures(&form_fields, form_signature);
+    AnnotateFieldsWithSignatures(&form_fields, form_signature,
+                                 password_form ? password_form.get() : nullptr);
   }
 
   std::vector<WebFormControlElement> unowned_elements =
@@ -567,7 +598,8 @@ void AnnotateFormsAndFieldsWithSignatures(WebLocalFrame* frame,
   WebString form_signature;
   if (password_form)
     form_signature = GetFormSignatureAsWebString(*password_form);
-  AnnotateFieldsWithSignatures(&unowned_elements, form_signature);
+  AnnotateFieldsWithSignatures(&unowned_elements, form_signature,
+                               password_form ? password_form.get() : nullptr);
 }
 
 // Returns true iff there is a password field in |frame|.
@@ -650,9 +682,6 @@ WebInputElement ConvertToWebInput(const WebFormControlElement& element) {
 ////////////////////////////////////////////////////////////////////////////////
 // PasswordAutofillAgent, public:
 
-const char kDebugAttributeForFormSignature[] = "form_signature";
-const char kDebugAttributeForFieldSignature[] = "field_signature";
-
 PasswordAutofillAgent::PasswordAutofillAgent(
     content::RenderFrame* render_frame,
     service_manager::BinderRegistry* registry)

components/autofill/content/renderer/password_autofill_agent.h

@@ -59,10 +59,6 @@ enum class PrefilledUsernameFillOutcome {
   kMaxValue = kPrefilledUsernameNotOverridden,
 };
 
-// Names of HTML attributes to show form and field signatures for debugging.
-extern const char kDebugAttributeForFormSignature[];
-extern const char kDebugAttributeForFieldSignature[];
-
 class RendererSavePasswordProgressLogger;
 class PasswordGenerationAgent;