[Password Generation] Use signatures for form matching

components/autofill/core/common/signatures_util.h

+// Copyright 2016 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.
+
+#ifndef COMPONENTS_AUTOFILL_CORE_COMMON_SIGNATURES_UTIL_H_
+#define COMPONENTS_AUTOFILL_CORE_COMMON_SIGNATURES_UTIL_H_
+
+#include <stddef.h>
+
+#include <stdint.h>
+#include <vector>
+
+#include "base/strings/string16.h"
+#include "components/autofill/core/common/form_data.h"

[vabr (Chromium), 2016/09/07 16:18:06]

This and the following #include seem like they could be just forward
declarations. If possible keep the #includes for the .cc files and use forward
declarations in the headers.

See
https://chromium.googlesource.com/chromium/src/+/master/styleguide/c++/c++.md...

[kolos1, 2016/09/08 08:34:28]

Done. Thanks.

+#include "components/autofill/core/common/form_field_data.h"
+#include "url/gurl.h"
+
+namespace autofill {
+
+typedef uint64_t FormSignature;

[dcheng, 2016/09/07 19:56:39]

Prefer using FormSignature = uint64_t in new code.

[kolos1, 2016/09/08 08:34:28]

Done.

+typedef uint32_t FieldSignature;
+
+// Calculates form signature based on |form_data|.
+FormSignature CalculateFormSignature(const FormData& form_data);
+
+// Calculates field signature based on |field_name| and |field_type|.
+FieldSignature CalculateFieldSignatureByNameAndType(
+    const base::string16& field_name,
+    const std::string& field_type);
+
+// Calculates field signature based on |field_data|. This function is a proxy to
+// |CalculateFieldSignatureByNameAndType|.
+FieldSignature CalculateFieldSignatureForField(const FormFieldData& field_data);
+
+// 64-bit hash of the string - used in FormSignature and unit-tests.
+uint64_t StrToHash64Bit(const std::string& str);

[vabr (Chromium), 2016/09/07 16:18:06]

optional nit: You defined an alias for this type (and on line 39). Do you want
to use it? If so, should the name also reflect that?

[kolos1, 2016/09/08 08:34:28]

Precisely, we use it not only for form signatures, but also for actino
signatures
(https://cs.chromium.org/chromium/src/components/autofill/core/browser/form_st...).
So, these 2 functions are more general. 

+
+// 32-bit hash of the string - used in FormSignature and unit-tests.
+uint32_t StrToHash32Bit(const std::string& str);
+}

[vabr (Chromium), 2016/09/07 16:18:06]

nit: Please add a blank line above the '}'.

[kolos1, 2016/09/08 08:34:28]

Done.

+
+#endif  // COMPONENTS_AUTOFILL_CORE_COMMON_SIGNATURES_UTIL_H_