Allow embedder to use custom cryptography in Autofill table.

components/autofill/core/browser/webdata/autofill_table.h

Index: components/autofill/core/browser/webdata/autofill_table.h
diff --git a/components/autofill/core/browser/webdata/autofill_table.h b/components/autofill/core/browser/webdata/autofill_table.h
index dc08b9b5ea82832be36792708e28d5e772ca7227..4966a6fb5ef16401e43cf6ca3d12a23a6b08b6b4 100644
--- a/components/autofill/core/browser/webdata/autofill_table.h
+++ b/components/autofill/core/browser/webdata/autofill_table.h
@@ -29,6 +29,7 @@ namespace autofill {
 class AutofillChange;
 class AutofillEntry;
 class AutofillProfile;
+class AutofillTableEncryptor;
 class AutofillTableTest;
 class CreditCard;
 
@@ -251,6 +252,8 @@ struct FormFieldData;
 class AutofillTable : public WebDatabaseTable {
  public:
   AutofillTable();
+  explicit AutofillTable(
+      std::unique_ptr<AutofillTableEncryptor> autofill_table_encryptor);

[Roger McFarlane (Chromium), 2017/02/22 22:50:52]

This additional public constructor seems redundant with the factory.

If the encryptor is exposed to the embedder via the factory delegate, then
there's not need for this constructor. the embedder just sets the delegate the
this class will do the right thing in getting the encryptor from the factory.

If the encryptor is taken as a constructor param, then the factory is redundant,
as the autofill construction call-sites could be updated by the embedder to
instantiate a different encryptor.

Is there a use case where this constructor is called, outside of constructor
delegation? If not, then just collapse this with the default constructor and
always use the factory.

[devarajn, 2017/02/22 23:10:54]

We can use this constructor to inject mocks in unit tests. Let me know what you
think?

[Roger McFarlane (Chromium), 2017/02/22 23:20:34]

The factory can also be used to inject mocks into the unittests, which also
serves to test the factory.

Let's get rid of this constructor.

[devarajn, 2017/02/22 23:26:05]

Alright. I will remove this constructor.

   ~AutofillTable() override;
 
   // Retrieves the AutofillTable* owned by |db|.
@@ -467,6 +470,8 @@ class AutofillTable : public WebDatabaseTable {
   static const size_t kMaxDataLength;
 
  private:
+  std::unique_ptr<AutofillTableEncryptor> autofill_table_encryptor_;

[please use gerrit instead, 2017/02/22 22:34:58]

Please move the variable below all methods. (Line 553.)

[devarajn, 2017/02/22 23:10:54]

Acknowledged.

+
   FRIEND_TEST_ALL_PREFIXES(AutofillTableTest, Autofill);
   FRIEND_TEST_ALL_PREFIXES(AutofillTableTest, Autofill_AddChanges);
   FRIEND_TEST_ALL_PREFIXES(