Support multi-value AD accounts custom attribute instead of single-value.

Bug: 1057855
Change-Id: I7a2ffbea114ffffefaaed2c011fb9de5fe7e1923
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2084032
Commit-Queue: Rakesh Soma <rakeshsoma@google.com>
Auto-Submit: Rakesh Soma <rakeshsoma@google.com>
Reviewed-by: Yusuf Sengul <yusufsn@google.com>
Cr-Commit-Position: refs/heads/master@{#746201}

chrome/credential_provider/gaiacp/gaia_credential_base.cc

@@ -179,9 +179,18 @@ HRESULT GetExistingAccountMappingFromCD(
     return hr;
   }
 
-  *sam_account_name = SearchForKeyInStringDictUTF8(
-      cd_user_response_json_string,
-      {kKeyCustomSchemas, kKeyEnhancedDesktopSecurity, kKeyADAccounts});
+  std::vector<std::string> sam_account_names;
+  hr = SearchForListInStringDictUTF8(
+      "value", cd_user_response_json_string,
+      {kKeyCustomSchemas, kKeyEnhancedDesktopSecurity, kKeyADAccounts},
+      &sam_account_names);
+
+  // Note: We only consider the first sam_account_name right now.
+  // We will expand this to consider all account names listed in the
+  // multi-value and perform username resolution in the future.
+  if (sam_account_names.size() > 0) {
+    *sam_account_name = sam_account_names.at(0);
+  }
 
   hr = SearchForListInStringDictUTF8(
       "value", cd_user_response_json_string,

chrome/credential_provider/gaiacp/gaia_credential_base_unittests.cc

@@ -1440,7 +1440,7 @@ TEST_F(GcpGaiaCredentialBaseAdScenariosTest,
   // Invalid configuration in admin sdk. Don't set the username.
   std::string admin_sdk_response = base::StringPrintf(
       "{\"customSchemas\": {\"Enhanced_desktop_security\": {\"AD_accounts\":"
-      " \"%ls\\\\\"}}}",
+      "[{ \"value\": \"%ls\\\\\" }]}}}",
       domain_name);
   fake_http_url_fetcher_factory()->SetFakeResponse(
       GURL(get_cd_user_url_.c_str()), FakeWinHttpUrlFetcher::Headers(),
@@ -1495,7 +1495,7 @@ TEST_F(GcpGaiaCredentialBaseAdScenariosTest,
   // Set valid response from admin sdk.
   std::string admin_sdk_response = base::StringPrintf(
       "{\"customSchemas\": {\"Enhanced_desktop_security\": {\"AD_accounts\":"
-      " \"%ls\\\\%ls\"}}}",
+      "[{ \"value\": \"%ls\\\\%ls\" }]}}}",
       domain_name, user_name);
   fake_http_url_fetcher_factory()->SetFakeResponse(
       GURL(get_cd_user_url_.c_str()), FakeWinHttpUrlFetcher::Headers(),