[AF] Integration tests for wallet metadata involving offline mode

This CL introduces several further integration tests for autofill wallet
metadata. All these tests involve "being offline" which is simulated by
the fake server returning errors.

This CL also changes the behavior in a minor way: it changes merging
two entities that have never been used. The change is non-controversial;
the main motivation for it is to allow writing crisper integration
tests.

Bug: 894001
Change-Id: I6e29c5ff8f96f6b40bb77f77e881ce1bb3ffbe25
Reviewed-on: https://chromium-review.googlesource.com/c/1335931
Commit-Queue: Jan Krcal <jkrcal@chromium.org>
Reviewed-by: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613053}

chrome/browser/sync/test/integration/wallet_helper.cc

@@ -83,7 +83,8 @@ bool ListsMatch(int profile_a,
     }
     Item* expected_item = &list_a_map[item->server_id()];
     if (expected_item->Compare(*item) != 0 ||
-        expected_item->use_count() != item->use_count()) {
+        expected_item->use_count() != item->use_count() ||
+        expected_item->use_date() != item->use_date()) {
       DVLOG(1) << "Mismatch in profile with server_id " << item->server_id()
                << ".";
       return false;

components/autofill/core/browser/credit_card.cc

@@ -1027,8 +1027,10 @@ std::ostream& operator<<(std::ostream& os, const CreditCard& credit_card) {
             << base::UTF16ToUTF8(credit_card.GetRawInfo(CREDIT_CARD_NUMBER))
             << " "
             << base::UTF16ToUTF8(credit_card.GetRawInfo(CREDIT_CARD_EXP_MONTH))
-            << " " << base::UTF16ToUTF8(
-                          credit_card.GetRawInfo(CREDIT_CARD_EXP_4_DIGIT_YEAR));
+            << " "
+            << base::UTF16ToUTF8(
+                   credit_card.GetRawInfo(CREDIT_CARD_EXP_4_DIGIT_YEAR))
+            << " " << credit_card.use_count() << " " << credit_card.use_date();
 }
 
 void CreditCard::SetNameOnCardFromSeparateParts() {