Allow embedder to use custom cryptography in Autofill table.

components/autofill/core/browser/webdata/autofill_table_encryptor_factory.cc

+// Copyright (c) 2017 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/webdata/autofill_table_encryptor_factory.h"
+#include "components/autofill/core/browser/webdata/system_encryptor.h"
+
+namespace autofill {
+
+AutofillTableEncryptorFactory::AutofillTableEncryptorFactory() {}
+
+AutofillTableEncryptorFactory* AutofillTableEncryptorFactory::GetInstance() {
+  return base::Singleton<AutofillTableEncryptorFactory>::get();
+}
+
+std::unique_ptr<AutofillTableEncryptor>
+AutofillTableEncryptorFactory::Create() {
+  if (delegate_) {

[Roger McFarlane (Chromium), 2017/02/17 21:04:08]

nit: no need for braces on single line if with no else

+    return std::move(delegate_->Create());

[Roger McFarlane (Chromium), 2017/02/17 21:04:08]

nit: no need for std::move on return values

[devarajn, 2017/02/17 22:28:54]

Done.

+  }
+
+  std::unique_ptr<AutofillTableEncryptor> encryptor(new SystemEncryptor());
+  return std::move(encryptor);

[Roger McFarlane (Chromium), 2017/02/17 21:04:08]

#inlcude "base/memory/ptr_util.h"
return base::MakeUnique<SystemEncryptor>();

// or...
return std::unique_ptr<AutofillTableEncryptor>(new SystemEncryptor());

// or...
return std::unique_ptr<SystemEncryptor>(new SystemEncryptor());

[devarajn, 2017/02/17 22:28:54]

Done.

+}
+
+void AutofillTableEncryptorFactory::SetDelegate(
+    std::unique_ptr<autofill::AutofillTableEncryptorFactory::Delegate>

[Roger McFarlane (Chromium), 2017/02/17 21:04:08]

nit: no need for autofill::
nit: no need for AutofillTableEncryptorFactory:: either, but the clarity is
nice, so meh...

[devarajn, 2017/02/17 22:28:54]

Done.

+        delegate) {
+  delegate_ = std::move(delegate);
+}
+
+}  // namespace autofill