Change AD username from forward slash to back slash

Bug: 1055726
Change-Id: Ibbdfdaff9c56175dd6f3b795f08b395f0f3bbcfc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2072118
Commit-Queue: Rakesh Soma <rakeshsoma@google.com>
Reviewed-by: Yusuf Sengul <yusufsn@google.com>
Reviewed-by: Tien Mai <tienmai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#744384}

chrome/credential_provider/gaiacp/gaia_credential_base.cc

@@ -254,8 +254,11 @@ HRESULT GetUserAndDomainInfo(
   // Login via existing AD account mapping when the device is domain joined if
   // the AD account mapping is available.
   if (is_ad_user) {
-    // The format for ad_upn custom attribute is domainName/userName.
-    const base::char16 kSlashDelimiter[] = STRING16_LITERAL("/");
+    // The format for ad_upn custom attribute is domainName\\userName.
+    // Note that admin configures it as "domainName\userName" but admin
+    // sdk stores it with another escape backslash character in it leading
+    // multiple backslashes.
+    const base::char16 kSlashDelimiter[] = STRING16_LITERAL("\\");
     std::vector<base::string16> tokens =
         base::SplitString(base::UTF8ToUTF16(sam_account_name), kSlashDelimiter,
                           base::TRIM_WHITESPACE, base::SPLIT_WANT_NONEMPTY);

chrome/credential_provider/gaiacp/gaia_credential_base_unittests.cc

@@ -1434,7 +1434,7 @@ 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/\"}}}",
+      " \"%ls\\\\\"}}}",
       domain_name);
   fake_http_url_fetcher_factory()->SetFakeResponse(
       GURL(get_cd_user_url_.c_str()), FakeWinHttpUrlFetcher::Headers(),
@@ -1489,7 +1489,7 @@ TEST_F(GcpGaiaCredentialBaseAdScenariosTest,
   // Set valid response from admin sdk.
   std::string admin_sdk_response = base::StringPrintf(
       "{\"customSchemas\": {\"Enhanced_desktop_security\": {\"AD_accounts\":"
-      " \"%ls/%ls\"}}}",
+      " \"%ls\\\\%ls\"}}}",
       domain_name, user_name);
   fake_http_url_fetcher_factory()->SetFakeResponse(
       GURL(get_cd_user_url_.c_str()), FakeWinHttpUrlFetcher::Headers(),