[Autofill Assistant] UT IsCompleteX

This adds unit tests for
* IsCompleteContact
* IsCompleteShippingAddress
* IsCompleteCreditCard

This change rearranges the |IsCompleteCreditCard| checks to be more
easily understandable without changing the behaviour of the function
as a whole.

Bug: none
Change-Id: I0ed6bc657737b69e362e588156d8befbbadacfd1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2214889
Commit-Queue: Sandro Maggi <sandromaggi@google.com>
Reviewed-by: Clemens Arbesser <arbesser@google.com>
Cr-Commit-Position: refs/heads/master@{#771701}

components/autofill_assistant/browser/user_data_util.cc

@@ -317,7 +317,8 @@ bool IsCompleteCreditCard(
     return true;
   }
 
-  if (!credit_card || !billing_profile) {
+  if (!credit_card || !billing_profile ||
+      credit_card->billing_address_id().empty()) {
     return false;
   }
 
@@ -334,8 +335,7 @@ bool IsCompleteCreditCard(
     return false;
   }
 
-  if (!credit_card->HasValidExpirationDate() ||
-      credit_card->billing_address_id().empty()) {
+  if (!credit_card->HasValidExpirationDate()) {
     return false;
   }
 
@@ -349,6 +349,7 @@ bool IsCompleteCreditCard(
           collect_user_data_options.supported_basic_card_networks.end()) {
     return false;
   }
+
   return true;
 }