[Password Generation] Use signatures for form matching

components/autofill/core/browser/autofill_field.cc

Index: components/autofill/core/browser/autofill_field.cc
diff --git a/components/autofill/core/browser/autofill_field.cc b/components/autofill/core/browser/autofill_field.cc
index 403be3659aea8c6111f61545d694d5fff70e6a4f..4dfedc99ad84dcff59ee492fff85fc42f0453a69 100644
--- a/components/autofill/core/browser/autofill_field.cc
+++ b/components/autofill/core/browser/autofill_field.cc
@@ -527,17 +527,6 @@ bool FillExpirationDateInput(const base::string16 &value,
   return true;
 }
 
-std::string Hash32Bit(const std::string& str) {
-  std::string hash_bin = base::SHA1HashString(str);
-  DCHECK_EQ(base::kSHA1Length, hash_bin.length());
-
-  uint32_t hash32 = ((hash_bin[0] & 0xFF) << 24) |
-                    ((hash_bin[1] & 0xFF) << 16) | ((hash_bin[2] & 0xFF) << 8) |
-                    (hash_bin[3] & 0xFF);
-
-  return base::UintToString(hash32);
-}
-
 base::string16 RemoveWhitespace(const base::string16& value) {
   base::string16 stripped_value;
   base::RemoveChars(value, base::kWhitespaceUTF16, &stripped_value);
@@ -643,10 +632,12 @@ bool AutofillField::IsEmpty() const {
   return value.empty();
 }
 
-std::string AutofillField::FieldSignature() const {
-  std::string field_name = base::UTF16ToUTF8(name);
-  std::string field_string = field_name + "&" + form_control_type;
-  return Hash32Bit(field_string);
+FieldSignature AutofillField::FieldSignature() const {
+  return CalculateFieldSignatureByNameAndType(name, form_control_type);
+}
+
+std::string AutofillField::FieldSignatureAsStr() const {
+  return base::UintToString(FieldSignature());
 }
 
 bool AutofillField::IsFieldFillable() const {