[Autofill] Control using Variations the sending of Autofill field metadata

components/autofill/core/browser/form_structure.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 "components/autofill/core/browser/form_structure.h"
 
 #include <utility>
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
 #include "base/i18n/case_conversion.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/metrics/field_trial.h"
 #include "base/sha1.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time/time.h"
 #include "components/autofill/core/browser/autofill_metrics.h"
 #include "components/autofill/core/browser/autofill_type.h"
 #include "components/autofill/core/browser/autofill_xml_parser.h"
 #include "components/autofill/core/browser/field_types.h"
@@ skipping 34 matching lines @@
 const char kBillingMode[] = "billing";
 const char kShippingMode[] = "shipping";
 
 // Strip away >= 5 consecutive digits.
 const char kIgnorePatternInFieldName[] = "\\d{5,}+";
 
 // A form is considered to have a high prediction mismatch rate if the number of
 // mismatches exceeds this threshold.
 const int kNumberOfMismatchesThreshold = 3;
 
+// Returns whether sending autofill field metadata to the server is enabled.
+bool IsAutofillFieldMetadataEnabled() {
+  const std::string group_name =
+      base::FieldTrialList::FindFullName("AutofillFieldMetadata");
+  return StartsWithASCII(group_name, "Enabled", true);
+}
+
 // Helper for |EncodeUploadRequest()| that creates a bit field corresponding to
 // |available_field_types| and returns the hex representation as a string.
 std::string EncodeFieldTypes(const ServerFieldTypeSet& available_field_types) {
   // There are |MAX_VALID_FIELD_TYPE| different field types and 8 bits per byte,
   // so we need ceil(MAX_VALID_FIELD_TYPE / 8) bytes to encode the bit field.
   const size_t kNumBytes = (MAX_VALID_FIELD_TYPE + 0x7) / 8;
 
   // Pack the types in |available_field_types| into |bit_field|.
   std::vector<uint8> bit_field(kNumBytes, 0);
   for (ServerFieldTypeSet::const_iterator field_type =
@@ skipping 26 matching lines @@
 
 // Helper for |EncodeFormRequest()| and |EncodeFieldForUpload| that returns an
 // XmlElement for the given field in query xml, and also add it to the parent
 // XmlElement.
 buzz::XmlElement* EncodeFieldForQuery(const AutofillField& field,
                                       buzz::XmlElement* parent) {
   buzz::XmlElement* field_element = new buzz::XmlElement(
       buzz::QName(kXMLElementField));
   field_element->SetAttr(buzz::QName(kAttributeSignature),
                          field.FieldSignature());
-  if (!field.name.empty()) {
-    field_element->SetAttr(buzz::QName(kAttributeName),
-                           base::UTF16ToUTF8(field.name));
+  if (IsAutofillFieldMetadataEnabled()) {
+    if (!field.name.empty()) {
+      field_element->SetAttr(buzz::QName(kAttributeName),
+                             base::UTF16ToUTF8(field.name));
+    }
+    field_element->SetAttr(buzz::QName(kAttributeControlType),
+                           field.form_control_type);
   }
-  field_element->SetAttr(buzz::QName(kAttributeControlType),
-                         field.form_control_type);
   parent->AddElement(field_element);
   return field_element;
 }
 
 // Helper for |EncodeFormRequest()| that creates XmlElements for the given field
 // in upload xml, and also add them to the parent XmlElement.
 void EncodeFieldForUpload(const AutofillField& field,
                           buzz::XmlElement* parent) {
   // Don't upload checkable fields.
   if (field.is_checkable)
     return;
 
   ServerFieldTypeSet types = field.possible_types();
   // |types| could be empty in unit-tests only.
   for (ServerFieldTypeSet::iterator field_type = types.begin();
        field_type != types.end(); ++field_type) {
     // We use the same field elements as the query and add a few more below.
     buzz::XmlElement* field_element = EncodeFieldForQuery(field, parent);
 
-    if (!field.autocomplete_attribute.empty()) {
-      field_element->SetAttr(buzz::QName(kAttributeAutocomplete),
-                             field.autocomplete_attribute);
+    if (IsAutofillFieldMetadataEnabled()) {
+      if (!field.autocomplete_attribute.empty()) {
+        field_element->SetAttr(buzz::QName(kAttributeAutocomplete),
+                               field.autocomplete_attribute);
+      }
+      field_element->SetAttr(buzz::QName(kAttributeAutofillType),
+                             base::IntToString(*field_type));
     }
-    field_element->SetAttr(buzz::QName(kAttributeAutofillType),
-                           base::IntToString(*field_type));
   }
 }
 
 // Helper for |EncodeFormRequest()| that creates XmlElements for the given field
 // in field assignments xml, and also add them to the parent XmlElement.
 void EncodeFieldForFieldAssignments(const AutofillField& field,
                                     buzz::XmlElement* parent) {
   ServerFieldTypeSet types = field.possible_types();
   for (ServerFieldTypeSet::iterator field_type = types.begin();
        field_type != types.end(); ++field_type) {
@@ skipping 1138 matching lines @@
   for (AutofillField* field : fields_) {
     FieldTypeGroup field_type_group = field->Type().group();
     if (field_type_group == CREDIT_CARD)
       field->set_section(field->section() + "-cc");
     else
       field->set_section(field->section() + "-default");
   }
 }
 
 }  // namespace autofill